The other think you'll want to use is to use M-x customize or M-x edit-options (in emacs) to customize/override the e-mail address that emacs' mail readers (RMAIL VM mh-e -- whichever) will put in its headers).

--Jim

REALBIOS?

From: Bill Dawson
Linux Wizard,
I am a newbie to Linux, and it has been a rocky start. Through a series of trial and error I discovered I needed to use loadlin to get started. When I ran loadlin I got this message:

"Your current configuration needs interception of "setup.S," but the setup-code in your image is *very* old (or wrong) Please use BIOSINTV/ REALBIOS or try another image file"

I looked at the reference on your page to REALBIOS, but it did not tell me where to find this program. Could you tell me where to get it and how to use it, please?

This happens when you have a memory manager, a disk manager, or any sort of TSR or device driver that "hooks" into your BIOS controlled interrupt vectors prior to running LOADLIN.

Short Answer:
-------------
Look for the loadlin.tar.gz package -- it should include that. Here's the URL for the copy of that on sunsite:

http://sunsite.unc.edu/pub/Linux/distributions/slackware/slakware/a4/loadlin.tgz

In this file there should be a copy of a program called REALBIOS.EXE which you would run as I've described before. It would create a special "system/hidden" file in the root of your C:\ drive -- which allows LOADLIN to find all the ROM handlers for each of your hardware interrupts.

One way you might avoid the problem is to invoke LOADLIN from your CONFIG.SYS. You can do that by invoking LOADLIN.EXE from a SHELL= directive in your CONFIG.SYS.

If you're using a version of MS-DOS later than 5.0 you can create a menu of boot options pretty easily -- see your MS-DOS/Windows '95 manuals for real details. Heres a trivial example:

                 rem CONFIG.SYS

                 menuitem WIN
                 menuitem LINUX
                 menudefault LINUX

                 [WINDOWS]
                 FILES=64
                 BUFFERS=32

                 [LINUX]
                 rem Load my 2.0.30 Linux kernel
                 SHELL=C:\LINUX\LOADLIN.EXE C:\LINUX\L2030.K root=/dev/hdc1

A bit of Background:
--------------------

PC Interrupt's are similar to Unix signals or Macintosh "traps." They are a table of pointers (in the first 4K of RAM) to "handlers" (routines that process verious sorts of events -- like characters coming in from the keyboard, handshaking signals from modems or printers, or data-ready events from disk drives). Normally, under MS-DOS, many of these events are handled by the BIOS. Others are handled by DOS device drivers. Still others aren't assigned to hardware events at all. In fact most of the interrupts are reserved for "service routines" (similar to Unix "system calls").

Linux doesn't use any of these routines. Your system's BIOS is a set of machine language routines written for the processor's "real mode." All x86 processor start in real mode. Every processor since the 286 has had a "protected" mode -- which is where all of the cool extended memory addressing and other features are implemented (actually the 286 only supported 24-bit addressing -- but it's not supported by any modern operating protected mode OS, the obscure 80186 was never used as the core processor).

So, your kernel has to shift from "real mode" to "protected mode." It also has to provide low level device drivers for any device you want to access -- where it uses I/O port and DMA channels to talk to the devices. The problem is that something from real mode must load the Linux kernel.

LILO and LOADLIN.EXE:
---------------------

The two common ways to load a Linux kernel into memory are: LILO and LOADLIN.EXE.

On any PC hard disk there is a "partition table" which is how multiple operating systems can share the same disk. This was necessary because the early design o fthe PC made it very difficult to swap drives. (Using the sorts of external SCSI drives that are common on other systems -- and any sort of OpenBoot or other PROM "monitor/debugger" -- makes it pretty easy to connect external drives with alternative OS' on them -- but that would have been far too expensive for the early PC XT's (the first PC's to offer hard drives).

Throughout most of the history of the PC architecture the BIOS for most machines could only see two hard drives -- any additional hard drives required additional drivers. Furthermore these two drives had to be on a single controller -- so you couldn't mix and match (without resorting to software drivers).

Worse than that -- there were no standard drivers -- each manufacturer had to write their own -- and none of them followed an particular conventions.

None of this matters to us, once we get the Linux kernel loaded, because Linux will recognize as many drives and devices as you attach to it (assuming you compile in the drivers or load their modules).

However, it does matter *until* we get our kernel loaded. With LILO this basically requires that we have our kernel somewhere where the BIOS can reliably find it from real mode. With LOADLIN we have a bit more flexibility -- since we can put the kernel anywhere where DOS can find it (after any of those funky drivers is loaded).

The partition table is a small block of data at the end of the master boot record (the MBR). It's about 40 bytes long and has enough for 4 entries. These are your "primary" partitions. One of them may be marked "active" that is will be the partition that is "booted" by default. One of the partitions may be an "extended" partition -- which is a pointer to another partition table on the same hard disk. The rest of the MBR (512 bytes total) which precedes the partition table is a section of real mode machine code called the 'boot loader'.

LILO can replace the MBR boot code (or it can be in the "logical boot record" -- which is like the "superblock" in Unix terminology -- it can also be placed in the boot sector of a floppy. If LILO is placed in "logical boot record" of a Linux partition -- then the DOS (or NT, or OS/2 or whatever) code must be set to load it (usually by setting that partition -- with LILO in it -- as the "active" partition).

With LOADLIN all of this is moot. You just boot DOS (or Win '95 in "command prompt" mode -- using {F8} during the boot sequence or whatever) -- or you can use the mult-boot configuration I described earlier.

One of the funny things about Linux is how many different ways you can load it. You can even shove a Linux kernel unto a floppy (using the dd command) and boot it that way (though you don't get any chance to pass it any parameters that way -- as you do with LOADLIN and LILO).

Last Notes:
-----------

Things are improving in the PC world. We no have some SCSI and EIDE controllers that can boot off of specially formatted CD-ROM disks (meaning we can use a full featured system for our rescue media, rather than and to scrimp and fight to get what we need onto one or two floppies). Most new systems come with at least EIDE -- giving us support for four devices rather than just two. (That's especially important when you want to share a system with a couple of OS and you want to have a CD-ROM drive). Any decent system comes with SCSI -- and most PCI SCSI controllers support 15 devices, rather than the traditional limit of seven. There are "removable bay" and drive adapters for IDE and SCSI -- so having an extra "cold spare" hard drive is pretty simple (and with SCSI we can have external drives again).

Conclusion:
-----------

There are still many cases where we need to use LOADLIN.EXE rather than LILO. I personally recommend that anyone that has DOS installed on their system make a LINUX directory somewhere and toss a copy of LOADLIN.EXE and their favorite kernel(s) in there. This makes an effective "alternative boot" sequence of your partition tables

--Jim

X-Windows Libraries

Date: Sun, 21 Sep 1997 14:06:26 -0700
From:

Although I did not get any response from you, I want to follow up with what I have found in the hopes that it may benefit someone along the way.

Sorry. The volume of my mail and the nature of my expertise (that is the fact that I don't know much about X Windows -- meaning I have to research anything I'm thinking of saying), means that there are sometimes unfortunate delays in my responses.

By the beginning of next year I hope to entirely revamp the way we do "The Answer Guy" (it will hopefully become "The Answer Gang").

This is about the problem of the X-Windows System not coming up but instead gives messages to the effect that it couldn't map the libraries.

In the process of our playing around, on occasion it would give a message about being out of memory. This puzzled us in that it was not consistent and appeared in a small percentage of the cases. However, on that clue, I found that the swap entry was missing from '/etc/fstab'. I manually turned on swapping and now the X-Windows System comes up and runs normally.

After adding the entry to '/etc/fstab', the whole system comes up and plays as it should. All I can say is that somewhere in the process of trying to get the system back on the air, the entry got removed!

Although you were not directly involved in the solution, I'd like to say, "Thanks for being there!"

I'm glad that worked. I'll try remember that next time a similar probl em comes up.

To the extent that I have "been there" you're welcome. As with most of the contributors to Linux I must balance my participation against my paying work. Naturally my contributions are far less significant than those of our illustrious programmers -- bit I hope to help anyway.

--Jim

PC Emulation

Date: Sat, 20 Sep 1997 13:07:56 -0700
From: SAFA ISAA

Hi Im working in comp. named Fordons Data our databas is a UNIX RS/6000.and we use aprogram calld Reflection to emulte pc so we can use the

That would be the WRQ Reflections to emulate a 3270 or 5150/5250 IBM terminal.

pc=B4s as aterminal.We use ethernet withe TCP/IP protcol=20 for com.betwen RS and PC .In pc we use win95.My q. is can we use doslinux or minilinux to com. withe rs instade of Reflection ??

You could install DOSLinux or MiniLinux and a copy of tn3270 and it *might* be able to talk to your RS/6000 (AIX) applications.

The problem is that the 3270 and 5150 terminals are very complex -- more of a client/server hardware than a "terminal/host." Essentially the IBM mainframes and mini's download whole forms to the "terminal" and the "terminal" then handles all sorts of the processing on its own.

tn3270 just implements a bare minimum subset of the 3270 protocols (just the weird EBCDIC character set so far as I know).

Frankly I don't know how this relates to your RS/6000 AIX system. That should be able to accept standard telnet and terminal connections. The question be becomes: "Can your database application (frontends) handle this sort of connection?" Does it provide a curses or tty interface?

If the answer is YES would U tell me where can I gat and how to test it..We R the bigest comp. in skandinavin for adm the hole car sys THX

This looks pretty mangled. The answer is "I don't know." However, Linux has the virtual of being free -- so there's very low risk in setting up a copy and trying it.

The more fundamental question is: What are you trying to accomplish? If you currently use Win '95 and Reflections why do you want to switch?

Do you want to save money?

While Win '95 and Reflections are commercial packages -- they aren't terribly expensive. Your administrative and personnel training costs are presumably much higher.

Is is for administrative flexibility?

The number one complaint about MS Windows products by Unix sysadmins (based on my attendance at LISA, USENIX, and similar events) is that MS products are difficult to administer -- and largely impossible to administer remotely or in any automated way.

Unix admins are spoiled by rlogin, rcp, rdist, and the fact that almost *anything* under Unix can be scripted. Most jobs are amenable to shell or perl scripts run via rlogin or cron -- and some of the "tough" jobs require expect (or the perl comm.pl) to "overcome those fits of interactivity."

Mouse driven interfaces with "floating" windows and dialog boxes are not "automation friendly" and MS Windows is particularly unfriendly in this regard. (MacOS has an Applescript and a popular third-party utility called QuickKeys (sp) that reduce its deficiencies in this area).

So, if you're considering switching from Win '95 to Linux so that you can centrally administer your client desktops -- it's probably not quite a compelling reason.

I could go on and on. The point is that you have to make a good business case for making this switch. Is there some Linux application that you intend to deploy? Is this suggested by your security needs? What are the requirements of you database applications? Could you migrate those to use "thin clients" (HTML/CGI forms) through a web (intranet) gateway? Could you implement the client on Java?

As for DOSLinux and MiniLinux specifically: Those can be pretty hard to find. I've sent e-mail to Kent Robotti, the creator of the DOSLinux distribution, to ask where it's run off to.

There are some other small Linux distributions that are suitable for installation into a DOS directory and able to be run off of the UMSDOS filesystem mount on '/' (root).

Mini-Linux is pretty old (1.2.x kernel) and doesn't appear to be currently maintained.

I'd look at Sunsite's distibutions directory --

http://sunsite.unc.edu/pub/Linux/distributions/

Normally there would be a doslinux directory thereunder -- but Kent seems to change things pretty rapidly and it may be that this as been removed while he's doing another upgrade or release.

It may be that you best bet would be the "Monkey" distribution (there's a directory under the URL above for that). This seems to be a five diskette base set in a set of split ARJ (Jung Archive) files. This seems to have been put together by Milan Kerslager of Czechloslovakia (CZ). There are about nine add-on "packages" that are ready to roll with it.

This is pretty recent (last March) package -- and one of the packages for it is a 2.0.30 kernel from the end of April.

A copy of ARJ.EXE doesn't seem to be included, so you'd have to grab that from someplace like:

Simtel: arj250a.exe -- Robert Jung's Archiver

ftp://ftp.cdrom.com/pub/simtelnet/msdos/arcers/arj250a.exe

* (for those who don't know Simtel used to be at the White Sands Missile Range on an old TOPS system. It's primary mirror used to be at oak.oakland.edu -- and it's now hosted by Walnut Creek CD-ROM (ftp.cdrom.com). If you need any sort of DOS shareware or freeware (perhaps to run under dosemu or Caldera's OpenDOS) this is the definitive collection. If you need any significant number of packages (like you need to test/evaluate a dozen of them to decide which works for you) I'd suggest springing for the CD. Another invaluable site for any non-MS DOS users is at http://www.freedos.org -- which in proper free software tradition has links to other DOS sites like RxDOS. DOS is truly the OS that wouldn't die -- and the shareware writers have about a decade headstart on ubiquitous availability over Linux).

--Jim

Visual Basic for Linux

Date: Thu, 18 Sep 1997 15:34:08 -0700
From: Forzano

I'm looking for a sw that can translate an application developed in Visual Basic to Unix. Could you help me?

The product you were undoubtedly thinking ofis VBIX by Halcyon Software (http://www.vbix.com). (408-378-9898).

I haven't used this product personally (since I have no interest in Visual BASIC). However they do claim to support Microsoft Visual BASIC source code and they offer some other, related products.

I see a DBIX (which appears to be a database engine with ODBC -- open database connectivity drivers for Linux/Unix and MS Windows '95 and NT). Also interesting might be their "BASIC 4 Java." Here's a blurb from their web pages:

"Halcyon Software Java Products

InstantBasic Script -Written in 100% Pure Java, Halcyon InstantBasic Script (IBS) is more than just cross-platform BASIC; it is BASIC for the Internet. Moreover, IBS is available as both a compiler and an interpreter, thus allowing developers to execute scripts as either BASIC source code or Java binaries(class file). The engine is compatible with Microsoft's BASIC Script Edition and provides complete Java Beans and ActiveX* support. The engine is easily customizable for quick integration and comes with its own lightweight Interactive Development Environment (IDE).

InstantBasic 4 Java - InstantBasic 4 Java is a 4GL development environment written 100% in Java that allows programmers to quickly and easily migrate their existing VB applications to run under any Java environments using the VB-like IDE.

--Jim

Linux 4.2 software and Hardware compatablity problems

I purchased a new computer system and 4.2 RedHat Linux Power Tools for my son, Blake, who is a student at Trinity University in San Antonio, TX.

They were purchased from different vendors.

Neither, Blake, his profs,myself or my vendor knew what we were doing. The result is a big mess. I believe the basic configuration is incorrect. That notwithstanding, I need to know which parts are not supported by Linux and recommended replacements. The following is a brief description of the system:

   Supermicro P5MMS motherboard with 430TX chip set. Ultra DMA 33 Mb/s
   Transfer and 512K pipe line burst mode cache

   AMD K6 MMX Processor @166 MHz, 6th generation performance, Microsoft
   certified.

   32 MEG SDRAN-10ns-DIMM Memory
   Western Digital 4.0 Gig IDE hard drive.  Split 50/50 by vendor
   TEAC 1.44 floppy disk drive
   MATROX MYSTIQUE 4MEG SGRAM PCI Video card
   14" NI SVGA Color monitor by MediaTech,
   1024X768-28DPI (I beleive it has a Fixed Frequency)
   PIONEER 24X CD ROM Drive
   Keytronics keyboard
   Microsoft PS2 mouse
   US Robotics 28.8/33.6 Sportster modem
   Sound Blaster AWE 64 sound card with speakers
   Windows 95 & Plus, Service release 2

When I have the correct equipment I will find a professional to properly configurer it.

Thank you for your assistance.

All of this equipment is fine. However I have to question your approach. There are several vendors that can ship you a fully configured system with Linux and Windows '95 pre-installed and configured (or just Linux, if you prefer).

In fact an upcoming issue of the Linux Journal has a hardware review of just such a system: the VAR Station II by VA Research (http://www.varesearch.com).
This system is very similar to the one you described (using the same video card, keyboard, and sound card and a very similar 24X CDROM). The big difference between the configuration you list and the one I reviewed is that the VAR Station came with a 4Gb SCSI hard drive, a Toshiba SCSI CD-ROM, and a SymBIOS SCSI adapter (in lieu of the IDE equipment you listed). Also the system I reviewed had a 3Com PCI ethernet card rather than any sort of modem (I already have some modem on my LAN). The other thing is that this motherboard is an Intel and uses a 266 Pentium II.

For about the same as you have spent on these parts separately you could probably get a system from VA Research or several others.

Here's a short list in no particular order:

PromoX (http://www.promox.com)

Aspen Systems (http://www.aspsys.com)

Linux Hardware Solutions (http://www.linux-hw.com)

SW Technology (http://www.swt.com)

Apache Digital (http://www.apache.com

Telenet Systems Solutions (http://www.tesys.com)

... and that doesn't include the ones that specialize in Alphas or SPARC based systems.

So, you have many choices for getting system with Linux preconfigured.

Now, if you're stuck with the system you've got, and you just want it all to work, you could pay a consultant to install and configure on the existing hardware. At typical rates of $50 to $150 per hour (mine are usually set at $91/hr) you'd rapidly spend more on this than on getting system from any of these vendors (who presumably have most of the installation and configuraiton process automated).

I cannot, in good conscience, recommend that you hire me to configure a system like this. It's just too expensive that way.

If you made it clear to your vendor that you intended to run Linux on the system, and they were unable to adequately install and configure it -- I personally think you are fully justified in returning everything and starting over. (If not then yo are still probably within your rights -- and you may still want to consider it).

Another approach you might try is to get just a hard disk with Linux pre-installed on it. This is the popular LOAD (Linux on a Disk) product from Cosmos Engineering (http://www.cosmoseng.com). This isn't quite a neat as getting the whole box pre-configured -- you still have to tell it what sort of video, sound, and other cards you want it to use (and you have to be able to support the extra drive -- which may be tricky if you have an IDE HD and an IDE CD-ROM drive already on your IDE controller. Many new IDE controller have two "channels" (enough to support four IDE devices) and some don't.

Another approach is to just let Blake fend for himself. He can wander around the campus a bit and look for fellow students who use and understand Linux. Who knows, he may meet some great people that way -- maybe even get a date in the process. Linux is very popular at colleges and universities -- and students are generally pretty enthusiastic about helping one another use any sort of toys -- computers especially.

--Jim

Moving /usr subdirectory to another drive..

My entire Linux filesystem currently resides on /dev/hda2 and uses up almost 90% of this partition. Because I am quickly running out of disk space on my original hard drive, I recently added a second hard drive and created a Linux partition on it which the system sees as /dev/hdb1. The /usr subdirectory of my filesystem has swollen to over 300MB, so I would like to copy all the directories and files under /usr over to /dev/hdb1 and then edit /etc/fstab so that this partition will then be mounted on /usr in the filesystem when I boot up.

I've given a lot of thought about how to do this, but I am very concerned about making this change because of the potential problems it might cause if not done properly. I would, therefore, appreciate your advice on how to proceed and what steps I should take to safeguard the integrity of my filesystem. BTW, I have a second, unused partition (/dev/hdb2) available on the new drive that could be used to store a "backup copy" of all the directories and files currently under /usr on /dev/hda2, and I also have an emergency boot/root floppy disk set that provides basic utilties.

Thanks very much for any help you can give me on this. Also, I want you to know that I enjoy your column in the Linux Gaxette and have found it to be very helpful.

Re: my previous columns and articles.

You're welcome.

Re: how to move (migrate) trees full of files:

I can understand you concerns. Under DOS and Windows this sort of operation is hairy, tricky, painful, and often terribly destructive.

The good news is that Unix is *much* better at this.

Here's the overview:

Mount the new filesytem to a temporary location Use a cpio or tar command to copy everything * (optionally) Make all these files "immutable" Boot from an alternate partition or a rescue disk Rename the source directory Make a new directory by that name (a mount point) Mount the new fs on the new mount point Update your /etc/fstab to make this permanent * (optionally) Update your tripwire database Test Remove the old tree at your leisure.

That's all there is to it. Now we'll go back over those steps in greater detail -- with same commands and some commentary.

Mount the new filesytem to a temporary location:

I like to use /mnt/tmp for this. So the command is:

mount /dev/hdb1 /mnt/tmp

Use a cpio or tar command to copy everything

I used to use tar for this -- but I've found that cpio is better. So here's the tricky command that's really the core of your question:

cd /usr/ && find . -print0 | cpio -p0vumd /mnt/tmp

* note: must do this as root -- to preserve permissions and ownership!

I realize this is an ugly looking command. However, we'll explain it step by step:

cd /usr/ && -- this cd's to the user directory and (if that goes O.K.) executes the following. If you typed /usr/ wrong you won't end up with a mess.

find . -print0 -- this provides a list of filenames as "null terminated strings" -- this will work *even if some of the files have spaces, newlines, or other dubious characters in them*. The results are written into a pipe -- and the program reading them must be capable of using this list. Luckily the GNU cpio and xargs command have this feature, as we'll see.

| cpio -p0vmd /mnt/tmp -- here's the tricky part. This is the "passthrough" mode of cpio. cpio normally copies files "in" or "out" -- but it can do "both" using the "passthrough" mode. cpio expects a list of filenames for its standard input (which we are providing with the 'find' command). It then copies the corresponding file "in" from the path specified (as part of the input line) and "out" to the the path specified as one of cpio's arguments (/mnt/tmp in this case).

The rest of the switches on this cpio command are: 0 -- expect the input records (lines) to be null terminated, v -- be verbose, m -- preserve the modification time of the files (so your next incremental backup does think that everything under /usr/ has suddenly changed), and d -- make leading directories as needed.

The last argument to this cpio command is simply the target directory we supply to the -p switch.

* (optionally) Make all these files "immutable"

One obscure feature of Linux' ext2 filesystem that I like to suggest is the "immutable attribute." This prevents *any* change to a given file or directory until the file is made "mutable" again. It goes way beyond simply removing write permissions via the standard Unix chmod command.

To do this use the command:

cd /mnt/tmp && chattr -R +i *

... or (to just do the files and not the directories):

find /mnt/tmp -type f -print0 | xargs -0 chattr +i

Ultimately this protects the sysadmin from his or her own 'rootly' powers. Even 'root' gets an "operation not permitted" error on any attempt to modify any feature of an immutable file.

Under normal circumstances this only marginally improves the system's security (any attackers who get a 'root' shell can just 'chattr' the files back to "-i" (mutable), and then have their way with your files). However, with the addition of the "sysctl securelevel" features that are expected in the 2.2 kernel (and may already be in the current 2.0 and 2.1 kernels) -- this will actually be a real security feature. (Discussion of "securelevel" is for a different article).

The point is that you can save yourself from many sorts of mistakes by making files immutable. This is particularly handy when running 'make' as root -- when you may have missed some problem in the file that would otherwise wipe out some of your important files. I suspect it's also handy if you get a bogus RPM package -- for basically the same reason.

(Many sysadmin's I've talked to and exchanged mail and news postings with fervently rail about the dangers of running make as root or using any sort of package management system. I understand their concerns but also recognize that the number of new inexperienced SA's -- and the sheer amount of work that many SA's are expected to complete -- practically require us all to take shortcuts and place some trust in some of the packages we're installing. So this "immutable" feature is a reasonable compromise).

Boot from an alternate partition or a rescue disk

Now we've done the hard part. All we have to do now is use the new copy of /usr. The only problem is that many of the commands we want to use require access to the shared libraries in /usr/lib. If you ever accidentally remove or damage /usr/lib/libc.so you'll have first hand experience with the problem.

So, we boot from an alternative boot partition or from a rescue disk, mount our normal root partition and continue. I'll leave out the details on this -- since the details vary from one distribution and site to another.

* Note to distributors and installation script maintainers: PLEASE INCLUDE AN OPTION TO CREATE AN ALTERNATIVE BOOT PARTITION IN YOUR PRODUCTS

Rename the source directory

Now we've copied the whole /usr/ tree to /mnt/tmp. We could just modify the /etc/fstab, and reboot the system. Your rc scripts would blithely mount the new /dev/hdb1 right over the existing /usr -- in effect "hiding" the old usr files. However this wouldn't be very useful -- it does free up any disk space.

So we issue a command like:

                        cd $NORMALROOT          # (wherever you mounted 
                                                # your normal root filesystem)
                        mv usr usr.old

Make a new directory by that name (a mount point)

Now we need to make a new /usr directory. We just issue the "mkdir /usr" command. However -- we're not quite done. We also want to chown and chmod this new directory to match the old one.

So we use "ls -ld usr.old" to see the owner, group, and permissions -- whice are typically like:

drwxr-xr-x  20 root     root         1024 Aug  1 22:10 usr

... and we use the commands:

                        chown root.root usr
                        chmod 755 usr

... to finish the new mount point.

(Personally I like to make /usr/ owned by root.bin and mode 1775 -- sticky and group writable. However, I also mount the whole thing read-only so I'm not sure this is comparable to any of the FSSTND (the filesystem standard) or the conventions used by any distribution).

I get a bit of confused about how the mount command works -- because it seems that the mount command actually over-rides the underlying ownership and permissions of the mount point. However I have seen problems that only seemed to go away when I make the underlying mount point match my intended permissions -- so I do it without understanding it completely.

Mount the new fs on the new mount point

I like to do this just to test things.

Update your /etc/fstab to make this permanent

Now you can edit your /etc/fstab (which should actually be under whatever mount point your using during this "alternative root/rescue" session)

You'll add a line like:

/dev/sdb1     /usr               ext2   defaults,ro 1 2

... to it.

(Note, I like to mount /usr/ in "read-only" mode. this provide one extra layer of protection from the occasional root 'OOOOPS!' It also helps enforce my policy that all new packages are installed under /usr/local, or /usr/local/opt (to which my /opt is a symlink), or under a home directory (which, on some of my systems are under /usr/local/home). The idea of maintaining this policy is that I know what files and packages are not part of the base OS).

* (optionally) Update your tripwire database

Tripwire is a program that maintains a detailed database of your files, their permissions, ownership, dates, sizes, and several different checksums and hashes. The intent is to detect modifications to the system -- in particular these would be signs of corruption, or tampering (security breaches or the work of a virus or trojan horse).

I won't go into details here. If you have tripwire installed, you want to update the database and store it back on it's read-only media.

For more info about tripwire see:

Tripwire (ftp://coast.cs.purdue.edu/pub/COAST/Tripwire)

To get it to compile cleanly under Linux look at the patch I wrote for it:

Tripwire Patch for Linux (http://www.starshine.org/linux/tripwire-linux.patch)

(no .html extension on that -- its just a text file).

(* one of these days I'll get around to writing up a proper web page for Tripwire and for my patch -- I submitted it to Gene and Gene and they never integrated it into their sources).

Test

Now you simply reboot under your normal configuration and test to your hearts content. You haven't removed the old /usr.old yet -- so you can back out of all your changes if anything is broken.

Remove the old tree at your leisure.

When you're satisfied that everthing was copied O.K. -- you can simply remove all the old copies using the command:

rm -fr /usr.old

Now you finally have all that extra disk space back.

Obviously this process can be done for other parts of your filesystems as well. Luckily any other filesystem (that doesn't include the / (root) and /usr/lib/ trees) is less involved. You shouldn't have to reboot or even switch to single user mode for any other migrations (though it won't hurt to do so).

I like to put /tmp, /var, and /usr/local all on their own filesystems. On news servers I put /var/spool/news on it's own. Here's a typical fstab from one of my systems:

# <device>    <mountpoint>   <filesystemtype> <options> <dump> <fsckorder>

/dev/sdc1      /                  ext2   defaults       1 1
/dev/sda6      /tmp               ext2   defaults       1 2
/dev/sda10     /usr               ext2   defaults,ro    1 2
/dev/sda7      /var               ext2   defaults       1 3
/dev/sda8      /var/log           ext2   defaults       1 3
/dev/sda9      /var/spool         ext2   defaults       1 3
/dev/sdb5      /usr/local         ext2   defaults       1 3

/proc          /proc              proc   defaults
/dev/sda2      none               swap   sw

/dev/fd0       /mnt/a             umsdos  noauto,rw,user 0 0
/dev/fd1       /mnt/b             umsdos  noauto,rw,user 0 0
/dev/hda1      /mnt/c             umsdos  defaults 0 0
/dev/scd1      /mnt/cd            iso9660 noauto,ro,user,nodev,nosuid 0 0
/dev/scd0      /mnt/cdwr          iso9660 noauto,ro,user,nodev,nosuid 0 0
/dev/fd0       /mnt/floppy        minix  noauto,rw,user,noexec,nodev,nosuid 0 0
/dev/fd0       /mnt/e2floppy      ext2   noauto,rw,user,noexec,nodev,nosuid 0 0
/dev/sdd1      /mnt/mo            ext2   noauto,rw,user,nodev,nosuid 0 0
/dev/sdd1      /mnt/mo.offline    ext2   noauto,rw,user,nodev,nosuid 0 0
/dev/sdd1      /mnt/modos         umsdos  defaults,noauto 0 0

tau-ceti:/      /mnt/tau-ceti   nfs     ro      

Note all the noauto and user point points. These allow users to access these removable devices without switching to 'root.' To protect against potential problems with the 'mount' command (being SUID 'root') I have it configured with the following ownership and permissions:

        -r-sr-x---   1 root     wheel       26116 Jun  3  1996 /bin/mount

Thus, only members of the "wheel" group are allowed to use the mount command (and I only put a few people in that). So I balance the risk of one of the "wheel" members finding and exploiting a bug in 'mount' vs. the expense having to do all mount's myself and risk of my typing *bad things* at the root shell prompt. I could also accomplish the same sorts of things with 'sudo' (and I use that for many other cases).

For more info about sudo see:

Sudo Home Page (http://www.courtesan.com/courtesan/products/sudo/)

FTP sudo: (ftp://ftp.cs.colorado.edu/pub/sysadmin/sudo

I hope that I've done more than answer your question. I hope I've given you some ideas for how to make your system more robust and secure -- how to apply some of the principles of "best practice" to administering your Linux box.

--Jim

C++ Integrated Programming Enviroment for X...

Dear Answer Guy,
I am a student in Information Systems at Kansas State University. As a relatively new user of Liunx, I was wondering if there exists a software package for X which could be comparable to something like Borland's C++ IDE? I've heard of something called Wipeout, but I'm not running Xview, is there anything else that I should check out?

I've never heard of "Wipeout" -- but it sounds suspicously like a slurred pronunciation of "wpe" -- which would be the "Window Programming Environment" by Fred Kruse. This has a console mode (wpe) and an X mode (xwpe) which are just links to the same binary.

I don't know that it requires Xview. Certainly on the rare occasions when I've run it I didn't have to do anything special -- just type the appropriate command for the mode I wanted and it just appears. So, I didn't have to install any special libraries or run a particular window manager or anything silly like that.

t typing 'xwpe &' from any xterm and see if that's already installed for you. If so you can add it to your window manager's menu tree, or to whatever sort of desktop manager or program/applications manager you use (or just always launch if from an xterm -- which is what I do for 90% of the things I run under X).

--Jim

LYNX-DEV new to LYNX

Will I be able to browse the FULL INTERNET using LYNX? I am using LYNX at my job, and the computer does not have window!

The web is not the FULL INTERNET!

Web browsers (such as Lynx, Mosaic, Netscape and MSIE) only access the web, ftp, and gopher. These are only a few of the services and protocols supported by the Internet.

There is no such thing as "browsing" the "full Internet." Indeed, the phrase "full Internet" is meaningless.

As to your implicit question:

Will you be able to browse all public web sites using Lynx?

... the answer is no.

Lynx is a browser that complies with as much of the HTTP and HTML specifications (the protocols and data representation (file formats) used by the "web") as possible -- within the constraints of it various platforms (text only -- no "inline" graphics, no sound, no support for "Java" or "JavaScript" (which aren't part of these specifications anyway).

Therein lies the rub. The client (Lynx) is able -- but many of the servers aren't willing. (In this case, by "servers" I'm referring to the people and the sites -- not the software).

Basically there are some sites that are "unfriendly." They make gratuitous use of tables, imagemaps, frames, Java applets, embedded JavaScript, cookies, ActiveX, active server pages (ASP) and ISAPI, and other extensions. They hope to win in some "one-up-manship" contest of "coolness."

Most of these extensions were introduced or promoted by one or another company (mostly Microsoft or Netscape) in their efforts to "capture" the "mindshare" -- which they hope will lead to increased *market*-share for their browsers and "web developement tools" (at the expense of standards, interoperability, and -- most especially -- their competitors).

The "web development tools" are the most insidious power piece in this little chess game. These tools (mostly Microsoft's "FrontPage") seem to include these non-standard extensions wherever possible -- with no warning, commentary, and mostly with no option to avoid them. Anyone who wants to produce "clean," friendly, standards conformant code is basically reduced to using a bare text editor -- and knowing the syntax inside and out.

In some particularly notorious cases there are "active" or "dynamic content" sites that will slam the door shut on your browser just based on a prejudice about it's name. By default your browser identifies itself to the server when fetching pages. Some sites are "just too cool" to have any textual content -- and shove a message down your throat:

"Go get a 'real' browser, punk!"

... (the sheer effrontery of telling your "customers" what sort of vehicle to drive around on the "stupor hypeway" -- it simply boggles the mind and gasts the flabber!).

I've even encountered a couple of cases where some "dynamic sites" would shove hundreds of kilobytes of "search engine spam" to my copy of Lynx. This was a crude effort to seed the databases maintained by Yahoo!, InfoSeek, HotBot, and others with excessively favorable content rating (based on the notion that most of these sites used "bots" (web robots, or "spiders") that identify themselves as "Lynx" (to avoid using the extra bandwidth on graphics that they couldn't use).

There are also an increasing number of sites that require SSL even for their non-secure information. SSL is a set of encryption protocols which are primarily used to provide for server-authenticated (or mutually authenticated) and "secure" (encrypted) access to web forms (mostly for order Pizzas without shouting your credit card number to every router in fifty states and a few countries).

So, there are a number of places on the "full Internet" that you can't adequately or comfortably browse with Lynx.

The good news is that Lynx does support features to address most of these problems. You can get an SSL proxy (which you'd run on the same machine as you run Lynx), the current versions of Lynx will list all the "frames" (which are a Netscape extension for displaying multiple separate HTML files concurrently), and can fetch some sorts of "map" files (the text files which describe the "hot" (clickable) regions of an IMAGEMAP -- which is a picture with "clickable" point therein) -- so you can browse them. Lynx can offer to accept cookies *(see note: cookies) for a given session -- and, eventually, may offer options to save them.

The bad news, again from the site maintainers and devlopers, is that they often don't provide meaningful names for their frames, or within their image map files. These are intended to be "seen" by a site's users -- and often aren't "seen" by the site's developers (remember the "integrated web developer software we mentioned earlier?).

The final bit of good news is this:

"Most sites that are particularly "Lynx-unfriendly" have not real content. When I succumb to curiosity and view them in a GUI browser -- they are all flash and no substance."

When we say "hypertext" they seem to hear "hype OR text"

So, Lynx acts as a bit of a twit filter. Visit a site first with a text browser (Lynx or emacs' W3 mode) and you'll know immediately whether their webmasters are hard of hearing or whether they "get it."

"* Cookies are another Netscape extension which are intended to allow web site developers a crude and unreliable way to "maintain state" (distinguish between users who might be at the same site -- like all of the AOL, CompuServe, and Netcom users going through their respective gateways). Marketing people drool over statistics based on "cookies" which can purport to tell how many *new* and *returning* users there are to a site, *who* read *which* documents other nonsense. However, for those statistics to be even close enough for a marketeer, the use of them must be almost universal (so we stop non-cookies browsers at the front home page) and we have to rely on them being so obscure in the browser software that no one tampers with them (they essentially must be "sneaky")."

PS: I've copied this to my editor at the Linux Gazette -- since I think it's a article for them to consider. Maybe they'll reprint it in "Websmith" (a feature of the Linux Journal, which is published by SSC, the maintainers for the Linux Gazette webazine). Interested parties can view all of the back issues of LG the URL in my sig. - -- a site that is emminently "Lynx Friendly"

-- Jim

"Linux Gazette...making Linux just a little more fun!"

Set your browser as wide as you'd like now.  I've fixed the Muse to expand to fill the aviailable space! © 1997 by

muse:  v; to become absorbed in thought  n; [ fr. Any of the nine sister goddesses of learning and the arts in Greek Mythology ]: a source of inspiration   elcome to the Graphics Muse! Why a "muse"? Well, except for the sisters aspect, the above definitions are pretty much the way I'd describe my own interest in computer graphics: it keeps me deep in thought and it is a daily source of inspiration.  [Graphics Mews] [WebWonderings][Musings] [Resources]

First, there are two new sections: Reader Mail and Web Wonderings. Reader Mail is an extension of Did You Know and Q and A.  I'm getting much more mail now than I did when I first started this column and many of the questions are worthy of passing back to the rest of my readers.  I've also gotten many suggestions for topics.  I wish I had time to cover them all.

Web Wonderings is new but may be temporary.  I know that many people are reading my column as part of learning how to do Web page graphics.  Its hard to deny how important the Web has become or how much more important it will become in the future.  I started reading a bit more on JavaScript to see if the language is sufficient to support a dynamically changing version of my Linux Graphics mini-Howto.  Well, it is.  I'll be working (slowly, no doubt) on converting the LGH to a JavaScript based set of pages.  My hope is to make it easier to search for tools of certain types.  I can do this with JavaScript, although the database will be psuedo static as an JavaScript array.  But it should work and requires no access to a Web server.

Readers with Netscape 3.x or later browsers should notice a lot more color in this column.  The Netscape 4.x Page Composer makes it pretty easy to add color to text and tables so I make greater use of color now.  Hopefully it will add more than it distracts.  We'll see. I may do a review of Netscape 4.x here or maybe for Linux Journal soon.  There are some vast improvements to this release of Netscape, although the new reader (known as Collabra Discussions) is not one of them.
 
      In this months column I'll be covering ...

• Browser detection using JavaScript
• SIGGRAPH 97 - what I saw, what I learned
• Designing Multimedia applications for Linux

VRML 98 The third annual technical symposium focusing upon the research, technology and applications of VRML, the Vritual Reality Modeling Language will be held Feb 16-19, 1998 in Monterey, California.  VRML 98 is sponsored by ACM SIGGRAPH and ACM SIGCOMM in cooperation with the VRML Consortium. Deadlines for submission are as follows:  Papers Mon. 22 Sep Panels Fri. 3 Oct Workshops Courses Video Mon. 2 Feb Contact Information:    VRML 98 Main Web Site http://ece.uwaterloo.ca/vrml98 Courses Workshops Panels Papers Video Submissions Demo Night		Iv2Rib Cow House Productions is please to present the first release of Iv2Rib, an Inventor 2.0 (VRML 1.0) to Renderman / BMRT converter. Source (C++) and an Irix 5.3 binary are available at:  http://www.cowhouse.com/ Home/Converters/converters.html  Additionally, new updates (V0.12, 30-Jul-97) of both Iv2Ray (the Inventor to Rayshade converter) and Iv2POV (the inventor to POVRAY converter) are also available on the same page, as both source (C++) and binaries for Irix 5.3 Crack released the Abuse source code to the public domain recently. Abuse was a shareware and retail game released for DOS, MacOS, Linux, Irix, and AIX platforms.  The source is available at    http://games.3dreview.com/abuse/files/abuse_pd.tgz    and    http://games.3dreview.com/abuse/files/abuse_pd.zip  If you don't know the 1st thing about Abuse,    http://crack.com/games/abuse    and    http://games.3dreview.com/abuse  Lastly, if you want to discuss the source (this is a just-in-case thing-it may very well not get used), we put a small newsgroup up at news://addicted.to.crack.com/crack.technical. That is also where we'll prolly host a newsgroup about Golgotha DLL's, mods, editting, movies and stuff like that later on.  Dave Taylor
Version 0.2.0 of DeltaCine DeltaCine is a software implemented MPEG (ISO/IEC 11172-1 and 11172-2) decompressor and renderer for GNU/Linux and X-Windows. It is available from ftp://thumper.moretechnology.com/pub/deltacine.  This project aims to provide portable C++ source code that implements the system and video layers of the MPEG standard.  This first release will interpret MPEG 1 streams, either 11172-1 or raw 11172-2, and render them to an X-Windows display.  The project emphasizes correctness and source code readability, so the performance suffers. It cannot maintain synchronized playback on a 166MHz Pentium.  Still, the source code contains many comments about the quality of the implementation and the problems encountered when interpreting the standard.  All of the executing code was written from scratch, though there is an IDCT (Inverse Discrete Cosine Transform) implementation adapted from Tom Lane's IJG project that was used during development.  This is an ALPHA release which means that the software comes with no warranties, expressed or implied.  It is being released under the GNU Public License for the edification of the GNU/Linux user community.  Limitations:  Requires ix86 No playback synchronization.  Movies play as fast as the decoder can render the frames. Requires X-Windows server in 16bpp mode. Features:  Full decode of Part 1 (System) and Part 2 (Video) specification for ISO/IEC 11172.  Full implementation except for synchronization. Reference quality output as compared to the Stanford implementation. User-mode multi-threading implemented as part of the decoder.		RenderMan Module v0.01 for PERL 5 This module acts as a Perl5 interface to the Blue Moon Rendering Tools (BMRT) RenderMan-compliant client library, written by Larry Gritz:  http://www.seas.gwu.edu/student/gritz/bmrt.html  REQUIREMENTS  This module requires Perl 5, a C compiler, and BMRT.  EXAMPLES  Some extra code has been added to the examples directory that should enable you to convert LightWave objects to RIB or to a Perl script using the RenderMan binding.  More useful examples will be provided in future releases.  Updates will hopefully be uploaded to PAUSE once I am authorized to upload there, and will be posted to my personal home page at:  http://www.gmlewis.com/  AUTHOR  Glenn M. Lewis |     Sven Neumann released two more GIMP scripts for the megaperls script collection. You can find them as usual at:  http://www-public.rz.uni-duesseldorf.de/ ~neumanns/gimp/megaperls  You'll need to patch the waves-plug-in if you want to use the waves-anim script. The patch was posted a while ago on the list but hasn't made its way into any semi-official release yet. It is also available from the web-site mentioned above.  Ed. Note:  Please note that the current release of the GIMP is a developers only release and not a public release.  If you plan on using it you should be very familiar with software development and C.  A public release is expected sometime before the end of the year.  Sven Neumann  <>

t1lib-0.3-beta

• t1lib is completely independent of X11 (although the program provided for testing the library needs X11)
• fonts are made known to library by means of a font database file at runtime
• searchpaths for all types of input files are configured by means of a configuration file at runtime
• characters are rastered as they are needed
• characters and complete strings may be rastered by a simple function call
• when rastering strings, pairwise kerning information from .afm-files may optionally be taken into account
• an interface to ligature-information of afm-files is provided
• rotation is supported at arbitrary angles
• there's full support for extending and slanting fonts
• new encoding vectors may be loaded at runtime and fonts may be reencoded using these encoding vectors
• antialiasing is implemented using three gray-levels between black and white
• a logfile may be used for logging runtime error-, warning- and other messages
• an interactive test program called "xglyph" is included in the distribution. This program allows to test all of the features of the library. It requires X11.

• draw directly into X11 drawbles
• respect fore- and background color of the graphics context
• provide opaque and transparent drawing mode
• provide automatic colored antialiasing

You can get t1lib by anonymous ftp at:
ftp://ftp.neuroinformatik.ruhr-uni-bocum.de/pub/software/t1lib/t1lib-0.3-beta.tar.gz

An overview on t1lib including some screenshots of xglyph can be found at:
http://www.neuroinformatik.ruhr-uni-bochum.de/ini/PEOPLE/rmz/t1lib.html
 

 GTK Needs A Logo!

The Prize

The prize for submitting the winning logo is a very cool [email protected] email alias. Thats right, if you win, you can be the envy of your friends with your sparkling @gimp.org email alias.

See http://www.gimp.org/contest.html for more details.
 

Announcing MpegTV SDK 1.0 for Unix MpegTV SDK 1.0 is the first toolkit that allows any X-windows application to support MPEG video without having to include the complex code necessary to decode and play MPEG streams.  MpegTV SDK 1.0 is currently available for:  Solaris 2.5 SPARC Solaris 2.5 x86 IRIX 6.2 Linux x86 BSD/OS 3.0 MpegTV also announces more good news: MpegTV Player 1.0 for Unix is now free for non-commercial use!  For more information on MpegTV products and to download MpegTV software, please visit the MpegTV website:  http://www.mpegtv.com  Regards,  Tristan Savatier - President, MpegTV LLC

Announcing MpegTV Plug-in 1.0 for Unix MpegTV Plug-in 1.0 is a streaming-capable Netscape Plug-in that allows you to play MPEG movie embedded inside HTML documents.  Unlike other similar Netscape Plug-ins (e.g. the Movieplayer Plug-in on SGI), MpegTV Plug-in is capable of streaming from the network, i.e. you can play a remote MPEG stream immediately, without having to wait for the MPEG file to be downloaded on your hard disk.  MpegTV Plug-in 1.0 is currently available for:  Solaris 2.5 SPARC IRIX 6.2 Linux x86 Solaris 2.5 x86 (coming soon) BSD/OS 3.0      (coming soon) Get it now at http://www.mpegtv.com/plugin.html !  Regards, -- Tristan Savatier (President, MpegTV LLC)  MpegTV:   http://www.mpegtv.com  MPEG.ORG: http://www.mpeg.org

USENIX 1998 Annual Technical Conference The 1998 USENIX Technical Conference Program Committee seeks original and innovative papers about the applications, architecture, implementation, and performance of modern computing systems. Papers that analyze problem areas and draw important conclusions from practical experience are especially welcome. Some particularly interesting application topics are:   ActiveX, Inferno, Java, and other embeddable environments   Distributed caching and replication   Extensible operating systems   Freely distributable software   Internet telephony   Interoperability of heterogeneous systems   Nomadic and wireless computing   Privacy and security   Quality of service   Ubiquitous computing and messaging  A major focus of this conference is the challenge of technology: What is the effect of commodity hardware on how we build new systems and applications? What is the effect of next-generation hardware? We seek original work describing the effect of hardware technology on software. Examples of relevant hardware include but are not limited to:   Cheap, fast personal computers   Cheap, large DRAM and disks   Flash memory   Gigabit networks   Wireless networks   Cable modems   WebTV   Personal digital assistants   Network computers  The conference will also feature tutorials, invited talks, BOFs,  and Vendor Exhibits.  For more information about this event:  * Visit the USENIX Web site:    http://www.usenix.org/events/no98/index.html  * Send email to the USENIX mailserver at [email protected].  Your message should contain the line:  "send usenix98 conferences".  * Or watch comp.org.usenix for full postings  The USENIX Association brings together the community of engineers, system administrators, scientists, and technicians working on the cutting edge of computing. Its technical conferences are the essential meeting grounds for the presentation and discussion of the most advanced information on new developments in all aspects of advanced computing systems.

Ra-vec version 2.1b - convert plan drawings to 3D vector format Ra-vec is a program which can convert plan drawings of buildings into a vector format suitable for the creation of 3D models using the popular modelling package AC3D. It is freely avalible for linux from  http://www.comp.lancs.ac.uk/ computing/users/aspinr/ra-vec.html    xfpovray 1.2.4 A new release of the graphical interface to the cool ray-tracer POV-Ray called xfpovray is now available.  It requires the most recent (test) version of the XForms library (0.87), and supports most of the numerous options of POV-Ray.  Hopefully 0.87 will migrate from test release to public release soon.  This version of xfpovray adds a couple nice features, such as POV-Ray templates to aid in writing scene files. Binary and source RPMs are also available.  Since xforms does not come in rpm, you may get a failed dependency error.  If you get this, just use the --nodeps option.  You can view an image of the interface and get the RPMs and source code from  http://cspar.uah.edu/~mallozzir/ There is a link there to the XForms home page if you don't yet have this library installed.  Bob Mallozzi <>    WSCG'98 - Call for Papers and Participation Just a reminder:  The Sixth International Conference in Central Europe on Computer Graphics and Visualization 98, in cooperation with EUROGRAPHICS and IFIP working group 5.10 on Computer Graphics and Virtual Worlds, will be held in February 9 - 13, 1998 in Plzen at the University of West Bohemia close to PRAGUE, the capital of Czech Republic  Information for authors: http://wscg.zcu.cz select WSCG'98  Contribution deadline:  September 30, 1997

ivtools 0.5.7

Source code at:
http://www.vectaport.com/pub/src/ivtools-0.5.7.tar.gz
ftp://sunsite.unc.edu/pub/Linux/apps/graphics/draw/ivtools-0.5.7.tar.gz

Linux elf binaries at:
http://www.vectaport.com/pub/src/ivtools-0.5.7-LINUXx.tar.gz
ftp://sunsite.unc.edu/pub/Linux/apps/graphics/draw/ivtools-0.5.7-LINUX.tar.gz

Web page at:
http://www.vectaport.com/ivtools/

Vectaport Inc.
http://www.vectaport.com

 

Pixcon & Anitroll 1.04

• added DOS binaries to the distribution
• 3DSMAX import/export plugin for Pixcon data files
• 25% increase in rendering speed

Why Pixcon & Anitroll?  Well, systems like Alias, Renderman, 3DS/3DSMAX, Softimage, Lightwave, etc are too expensive for average users (anywhere from $1000 - $5000 US)  and require expensive hardware to get images in a reasonable amount of time.  Conventional freeware systems, such as BMRT, Rayshade, and POV are too slow (they're raytracers...). Pixcon & Anitroll is FREE, and doesn't take a long time to render a frame (true, its not real time... but I'm working on it). It also implements some rendering techniques that were presented at Siggraph 96 by Ken Musgrave and was used to generate an animation for Siggraph '95.

The Pixcon & Anitroll Home page is at: http://www.radix.net/~dunbar/index.html

Comments to
Availabe from:  ftp://sunsite.unc.edu/incoming/Linux/pixcon-105.tgz
and will be moved to:
ftp://sunsite.unc.edu/pub/Linux/apps/graphics/rays/pixcon-105.tgz
 

Glide 2.4 ported to Linux

To quote 3Dfx's web page:

Glide is an optimized rasterization library that serves as a software 'micro-layer' to the 3Dfx Voodoo accelerators. With Glide, developers can harness the power of the Voodoo to provide perspective correct, filtered, and MIP mapped textures at real-time frame rates - without having to work directly with hardware registers and memory, enabling faster product development and cleaner code.

For more information on Glide please see:
http://www.3dfx.com/download/sdk/index.html
For more download informtion for Glide see:
http://www.3dfx.com/download/sdk/index.html
For more information on Mesa see:
http://www.ssec.wisc.edu/~brianp/Mesa.html
For an FAQ on 3Dfx on Linux see:
http://www.gamers.org/~bk/xf3D/
Finally, if you need to discuss all this, try the 3Dfx newsgroup:
news://news.3dfx.com/3dfx.glide.linux
 

Did You Know?

Q and A

A: JPEG, to my knowledge, doesn't support transparency.  You have to use GIF (or PNG).  GIF files can have a transparency added by picking the color you want to be transparent.  One of the colors, and only one, can be specified as transparent.  You can use xv to pick the color.  Then you can use the NetPBM tools to convert the image to a transparent GIF.  You would do something like

Check the man page for ppmtogif for how to specify the color to use.
 

Reader Mail

At the end of your gamma correction discussion of graphics muse issue 17, you mention that you were unable to find contact info for Greg Ward. He is at (he is now Greg Ward Larson-> believes in reciprocating on the maiden-married name thing).However, a better link is to the radiance page: a high-end, physically correct ray-tracing/radiosity renderer used mostly for architectural design (and runs on Linux! Free source!)  http://radsite.lbl.gov/radiance/HOME.html

I had just finished reading your article in LJ about Megahedron and I was reading some of the examples and playing with them.  I looked in mhd/system/smpl_prims and found the following: coord_system=right_handed; so you can do this picture smokey_train_pic with         coord_system=left_handed; Notice than I put it just under the declaration of the top level object (the one called by do). Of course if you use this for the examples provided you will notice that now the camera is not focusing on the subject.

Usually I skip over the Graphics Muse, (I'm a bit head, not a graphic artist) but something drew me in this time.  Perhaps it's because I'm investigating the development of a Linux based Distance Learning platform for for use in my networking classes.Anyway, one of the  least expensive resources I've found over time has been the Winnov Videum-AV.  An outstanding card but near as I can tell, there are no Linux drivers .  I contacted Winnov a while back and they're not interested in Linux at all, but after reading about the efforts of the QuickCam folks I was wondering if you could just mention that the Videum card exists, perhaps simply asking if anyone is working on a driver?  (And, no, I don't own stock in Winnov nor know anyone that does.)Perhaps some of the programmers out there are working on something, or maybe Winnov will take the hint.  I'm certain that a Videum card on Linux would outperform the same card under NT.  Imagine a streaming video service (Either Java based or using the just released 60 stream Real Video Linux server) with a live feed under Linux. Sure wish the folks at Winnov could!Anyway, thanks. The 'Muse has a good balance of technical material and artistic issues.  I'll be reading the 'Muse a lot more often, but first...... the back issues!

Jim Tom Polk  <>  http://camalott.com/~jtpolk/ wrote:

Reading your column I noticed that you state that you don't know of any animated GIF viewers for Linux. I use xanim.  I usually use gifmerge to create the image, and then load up the image and step through it with xanim.  I also find it useful to see just how some animations are composed / created.  The version I have installed is: XAnim Rev 2.70.6.4 by Mark Podlipec (c) 1991-1997 I only found it out by accident when I loaded an animated GIF by accident (I was clicking on an mpeg file and missed it). You can start/stop/pause.  Go forward and backwards one frame at a time, and speed up or slow down the entire sequence.  You still have to use another utility to create the GIF, but I use it all the time.Really enjoy your column.

Alf Stockton <> wrote:

I have a number of JPEGs that I want to add external text to. ie Comments on photographs I have taken with my QV-10 digital camera. Now I don't want the text to appear on the picture. It must appear either next to or below same. So in other words I want to create a large JPEG consisting of some text and my picture. Of course it does not necessarily have to be a JPEG but it must be something that a web browser can display as I intend uploading same to my ISP.The thought was that I would create a HTML document for each image and this would work but now I have a large number of images & I don't want to create an equal amount of HTMLs.

If you want the text visible but not overlapping the original image there are lots of ways to get it done.  I highly recommend the GIMP, even though you feel its overkill - once you've learned to use it you'll find it makes life much easier.  However, if you just want a shell script to do it you can try some of the NetPBM tools.  NetPBM is a whole slew of simple command line programs that do image conversion and manipulations.  One of the tools is pnmcat.  To use this you'd take two images and convert them to pnm files.  For GIFs that would be like

Then you use pnmcat like this:

This would place the two images side by side.  You could then convet this back to a GIF file for placing on the Web page.  pnmcat has other options allowing you to stack the images (-topbottom) and specify the way to justify the smaller image if the images are not the same width/height. There is a man page for pnmcat that comes with NetPBM.

Note that the NetPBM tools do not have tools for dealing with JPEG images. However, there are some tools called jpegtoppm and ppmtojpeg available from the JPEG web site (I think).  I'm not positive abou that.  I don't use these specific tools for dealing with JPEGs.

If you want, you can always read in the JPEG with xv first and save it as a PPM/PNM (these two formats are essentially the same) file first, then use the NetPBM tools.

Jeff Taylor <> wrote:

1)  You mentioned [in your review of Megahedron in the September issue of Linux Journal]some difficulty in writing the model information to a file for rendering with an alternative renderer.  This is important to me as I would like to use PVMPOV for the final rendering.  It wasn't clear from what you wrote, is it difficult to do or impossible?

2)  Does the modeller allow 2D images to be printed?  I'm thinking of CAD type 3-angle-view drawings.  I'd like to use it for CAD applications where a model is created and scale drawing can be printed.

Daniel Weeks <> wrote:

I just want to start of by telling you that you are doing a great job with the Graphic Muse and on the current article in the Linux Jornal on Megahedron.  This is where my questions come from.

First, with Megahedron I noticed that it is a progamatic/procedural language for modeling (interestingly enough the language itself is not that dissimilar to our cgiStudio language in structure and function {except for that wierd commenting style}, in fact I already have a perl script that translates most of SPML to cgiStudio :).  The question here is does Megahedron have any sort of interface over the demo mode, I guess I mean something like (but it doesn't have to be as fully functional or bloated as) SoftImage or Alias|Wavefront.  Second can Megahedron support NURBS patches and deforming geometry.

Hap Nesbitt <>, of Handmade Software wrote in reply to my review of Image Alchemy:

A very nice review thanks.  BTW we do 81 formats now.  The new formats are documented in addendum.pdf. The Mews seems quite ambitious.  Is this all your work or do you get some help?

We've found a tool for porting Mac libraries to X. Our Mac interface is beautiful and we should get it ported sometime in the next 6 months or so.  I'll keep you posted. BTW people don't really buy much Image Alchemy, they buy Image Alchemy PS to RIP PostScript files out to large format inkjet plotters in HP-RTL format. If you give me your mailing address I'll send you a poster done this way. I think you might enjoy it.

G. Lee Lewis <> wrote:

Your web pages look really nice.

Did you use Linux software to create your web pages?

Can you say what you used?.

What flavor of Linux do you like, redhat, debian, etc..??

I've not seen the Debian distribution yet.  Slackware is also quite good. I liked their "setup" tool for creating packages for distribution because it used a simple tar/gzip/shell script combination that was easy to use and easy to diagnose.  However, its not a real package management system like RPM.  "Consumers" (not hackers) will probably appreciate RPM more than "setup".

I also use commercial software for Linux when possible.  I run Applixware, which I like very much, and Xi Graphics AcceleratedX server instead of the XFree86 servers.  The Xi server is much easier to install and supports quite a few more video adapters.  However, it doesn't yet support the X Input Extension unfortunately.  The latest XFree86 servers do, and thats going to become important over the next year with respect to doing graphics.

What do you think of Caldera OpenLinux?

Of all the distributions Caldera probably has a better understanding of what it takes to make a "product" out of Linux - something beyond just packing the binaries and sticking them on a CD.  A successful product will require 3rd party products (ones with full end-user quality, printed documentation and professional support organizations) and strategic alliances to help prevent fragmentation.  Fragmentation is part of what hurt the early PC Unix vendors (like Dell and Everex) and what has plagued Unix workstation vendors for years.

So, in summary, I strongly support the efforts of Caldera, as well as Red Hat, Xi Graphics, and all vendors who strive to productize Linux.

<> wrote:

Is there some documentation available on GIMP - please, please say there is and point me towards it.

There will be a 4 part series on the GIMP in the Linux Journal starting with the November issue.  I wrote this series.  It is very introductory but should help a little. I also did the cover art for that issue.  Let me know what you think!

You can also grab any Photoshop 3 or Photoshop 4 book that covers the basics for that program.  The Toolbox (the main window with all the little icons in it) is nearly exactly the same in both programs (GIMP and Photoshop).  Layers work the same (with some minor differences in the way the dialog windows look).  I taught myself most of what I know based on "The Photoshop 3 Wow! Book" and a couple of others.

Browser Detection with JavaScript

CSS is about to make web pages a whole lot more interesting.

The down side to CSS is that its new.  Any new technology has a latency period that must pass before the technology is sufficiently distributed to be useful to the general populace.  In other words, the browsers aren't ready yet, or will just be released at the time this goes to print, so adding CSS elements to your pages will pretty much go unnoticed for some time.  I would, however, recommend becoming familiar with them if you plan on doing any serious Web page design in the future.  In the meantime we still have our JavaScript 1.1 and good ol' HTML 3.0.

Ok, enough philosophizing, down to some nitty gritty.

I just updated my GIMP pages to reflect the fact that the 0.54 version is pretty much dead and the 0.99 version is perpetually "about to become 1.0".  What that means is I've dropped most of my info and simply put up a little gallery with some of the images I've created with the GIMP.  Along with the images, including a background image that was created using nothing more than a set of gradients created or modified with the gradient editor in the GIMP, I've added some Javascript code to spice up my navigation menus and a couple of simple animated GIFs.  It was probably more fun to do than it is impressive.  If you check out these pages you'll find its a little more attractive with Netscape 4.x since I'm using a feature for tables that allows me to specify background images for tables, rows and even individual cells.  Netscape 3.x users can still see most of the effects, but a few are lost.

I had added some JavaScript code to the main navigation page of my whole site some time back.  I sent email to my brother, who does NT work at Compaq, and a Mac-using friend asking them to take a look at it and see what they thought.  It turned out MSIE really disliked that code and the Netscape browser on the Mac didn't handle the image rollers correctly (image rollovers cause one image to be replaced by another due to some user initiated action - we'll talk about those in a future Web Wonderings).  Shocking - JavaScript wasn't really cross platform as was first reported.  Well, its a new technology too.  The solution is to add code to determine if the rest of the code should really execute or not.  I needed to add some browser detection code.

That was .... a year ago?  I can't remember, its been so long now.  Well, while scanning the CSS and other info recently I ran across a few JavaScript examples that explained exactly how to do this.  I now take this moment to share it with my readers.  Its pretty basic, so I'll show it first, then explain it.   Note:  the following columns might be a little hard to read in windows less than about 660 pixels wide.  Sorry 'bout that.
 

SIGGRAPH 97

Designing Multimedia Applications I recently picked up a copy of Design Graphics from my local computer bookstore.  This is a monthly magazine with a very high quality layout that covers many areas of computer graphics in great detail.  The magazine is rather pricey, about $9US, but so far has proven to be worth the price.  If you are into Graphic Design and/or User Interface Design it might be worth your time and money to check out this magazine. The July issue focused on MetaCreations, the company that was created from the merger of MetaTools and Fractal Design.  MetaTools founders includeKai Krause, a unique designer and software architect, the man responsible for the bold interfaces found in MetaTools products like Soap and GOO.  This issue also included very detailed shots of the interface for Soap.  It was while reading this issue and studying the interface for Soap that I realized something basic:  Multimedia applications can look like anything you want.  You just have to understand a little about how Graphical Interfaces work and a lot about creating graphical images. Graphical Interfaces are simply programs which provide easily recognizable displays that permit users to interact with the program.  These interfaces are event driven, meaning they sit in a loop waiting for an event such as a mouse click or movement and then perform some processing based on that event.  There are two common ways to create programs like this.  You can use a application programming interface, often referred to as an API, like Motif or OpenGL.  Or you can use a scripting interface like HTML with Java/JavaScript or VRML.  Which method you choose depends on the applications purpose and target audience. So, who is the target audience?  My target audience for this column is the multitudes of Linux users who want to do something besides run Web servers.  Your target audience will either be Linux/Unix users or anyone with access to a computer no matter what platform they use.  In the first case you have a choice:  you can use either the API's or you can make use of HTML/VRML and browser technology.  If you are looking for cross-platform support you will probably go with browser technology.  Note that a third alternative exists - native Java which runs without the help of a browser - but that this is even newer than browser technology.  You'll have about a year to wait till Java can be used easily across platforms.  Browser technology, although a little shakey in some ways, is already here. In order to use an API for your multimedia application you need to choose a widget set.  A widget set is the part of the API that handles windowing aspects for you.  Motif has a widget set that provides 3D buttons, scrollbars, and menus.  Mutlimedia applications have higher demands than this, however. The stock Motif API cannot handle MPEG movies, sound, or even colored bitmaps.  It must be used in conjunction with OpenGL, MpegTV's library, the OSS sound interface and the XPM library to provide a full multimedia development environment.  The advantage to the API method is control - the tools allow the developer the ability to create applications that are much more sophisticated and visually appealing than with browser based solutions.  An API solution, for example, can run in full screen mode without a window manager frame, thus creating the illusion that it is the only application running on the X server.  In order to get the effects you see in MetaTool's Soap you will need to create 2D and 3D pixmaps to be used in Motif label and button widgets.  If you do this you should turn off the border areas which are used to create Motif's 3D button effects. You will also need to write special callbacks (routines called based on an event which you specify) to swap the pixmaps quickly in order to give the feeling of motion or animation. Even with the use of 3D pixmaps in Motif you still won't have the interactivity you desire in your multimedia application.  To add rotating boxes and other 3D effects with which the user can interact you will need to embed the OpenGL widget, available from the MesaGL package, into your Motif program.  By creating a number of OpenGL capable windows you can provide greater 3D interactivity than you can by simply swapping pixmaps in Motif labels and buttons.  The drawback here is that you will be required to write the code which registers events within given areas of the OpenGL widget.  This is not a simple task, but it is not impossible.  Using OpenGL with Motif is a very powerful solution for multimedia applications, but it is not for the faint of heart developer. Using browser technology to create a multimedia application is a little different.  First, the browser will take care of the event catching for you.  You simply need to tell it what part of a page accepts events, which events it should watch for and what to do when that event happens.  This is, conceptually, just like using the API method.  In reality, using a browser this way is much simpler because the browser provides a layer of abstraction to simplify the whole process.  You identify what parts of the page accept input via HTML markup using links, anchors, and forms and then use JavaScript's onEvent style handlers, such as onClick or onMouseOver, to call an event handler.  Formatting your application is easier using the HTML markup language than trying to design the interface using the API.  You can have non-rectangular regions in imagemaps, for example, that accept user input.  API's can also have non-rectangular regions, but HTML only requires a single line of code to specify the region.  An API can use hundreds of lines of code. -Top of next column-

More Musings...   No other musings - what?  This wasn't enough for you?  <grin>   Ok, since we know using API's can be complex, and because I'm going to run out of room long before I can cover how to use an API to do a multimedia application, lets look at creating an application using browser technology. Creating web pages is pretty easy.  If you haven't had a chance yet, take a look at Netscape 4.0.  It includes a tool called the Page Composer which allows for WYSIWYG creations of web pages.  This column was created using Page Composer.  Web pages are not enough, of course.  We need graphics, animations and sound.  Not to mention interaction with files on disk. Graphics, animations and sound can easily be embedded in a web page with links.  Your application will probably need to provide players for any animations or sounds you provide unless you feel really confident users will already have players.   For animations on Linux systems, other than animated GIFs which are supported natively in most browsers these days, you can try xanim.  Your installation process will have to explain how to install the players.  JavaScript does permit you to query what players and plug-ins are available but doesn't appear to give you the ability to automatically launch them without having first registered them with the browser. Sound can be added just like the graphics and animations.  You simply have links to the sound files.  Not all Linux systems will have sound available.  You might want to consider writing a plug-in which checks for the sound devices before trying to play sounds and having this plug-in installed for your sound files.  Security issues may prevent a plug-in from opening a device file.  You should check the Netscape plug-in API to find out what files you can and cannot open. You might be wondering how you can use a browser for a multimedia application on a CD.  Don't forget - both MSIE and Netscape allow you to view HTML documents on the native system.  On Netscape you can just use something like file:/cdrom/start.html to open up the main page of the application.  Any links - sound, graphics, or animations - can be displayed or played when the page is first loaded using JavaScript's onLoad event handler.  Graphics, animations, sound and Java applets do not have to be served via a Web server to be viewed or run by the browser.  And JavaScript is embedded in the HTML page so it doesn't require a Web server either.  As long as you use relative links (relative to the directory where your applications start page is located) your users won't need access to a Web server to use your HTML-based multimedia application. Well, we've covered just about all the things you'll want to do in your program except how to access files.  Security in browsers and with Java has traditionally been rather zealous - the systems were secure by denying all access to your hard drives.  Thats still the case even with JavaScript 1.2.  There are no real file I/O commands in the JavaScript language.  In order to place data in your application you will need to place it all in static arrays embedded in JavaScript code in a page.  Fortunately you can place this data in separate files and link to them when the page is loaded.  To do this you would use the SRC= attribute of the SCRIPT tag.  Netscape 3.0 or later browsers will read this and load the script file as if it were embedded at the SCRIPT tag of the original page.  This will not work for pre-3.0 browsers, some of the beta 4.0 browsers or (apparently) any of the MSIE browsers. The SCR attribute  provides some level of control for maintaining your data files, but it also means your data is in user readable files on the CD. If you use Java applets instead you have the ability to compile this data into an object file but you still don't have access to your file system.  It may be possible to read data from files using plug-ins in order to perform some interactive operations but I'm not familiar with the Netscape or MSIE plug-in API's and suspect they also have some measure of security that may prevent this.  Reading files seems harmless enough, but there are reasons to disallow this practice. There is a way to get read/write access to the users filesystem from a JavaScript or Java application - certificates.  This is a new technology and I'm not that familiar with its use yet.  The Official Netscape JavaScript 1.2 Book describes certificates and how to obtain and create them.  I suggest taking a look at this book (at the end of chapter 14) if you are interested in this. As I reread this article I realize what is so crystal clear in my mind now is probably still a muddy swamp to my readers.  Don't fret.  I covered a lot of material in a rather short space.  What you should do is first pick a method - API or browsers.  Then pick one part of that method and start reading all you can about it.  Personally, I understand the API methods better since I'm a programmer by trade.  The browser technology is interesting in that it provides the User Interface (UI) that is filled in by the developer with images and sound.  Abstrasting the UI in this manner is the future of applications but its still in its early days of development.  In either case you still need an understanding of what each piece of the puzzle does for you. The API method will give you more control and access to databases without the need for servers (you can embed the database code in the application).  The browser method is easier to prototype and develop but has limited access to the system for security reasons. Either method can produce stunning effects, if you understand how all the pieces fit together.  And when you look at MetaCreations products, like Soap and GOO, you can see the kinds of effects that are possible.

Linux Graphics mini-Howto  Unix Graphics Utilities  Linux Multimedia Page  Some of the Mailing Lists and Newsgroups I keep an eye on and where I get alot of the information in this column:  The Gimp User and Gimp Developer Mailing Lists.  The IRTC-L discussion list  comp.graphics.rendering.raytracing  comp.graphics.rendering.renderman  comp.graphics.api.opengl  comp.os.linux.announce

Future Directions

• Web Wonderings - Adding JavaScript Rollovers to simulate dynamic images
• My SIGGRAPH notes, if I can get my notebook running again.
• Maybe a look at libgr, if I have time.

"Linux Gazette...making Linux just a little more fun!"

Linux Benchmarking - Concepts

by André D. Balsa

With corrections and contributions by Uwe F. Mayer and David C. Niemi

1. Basic concepts and definitions

• 1.1 Benchmark
• 1.2 Benchmark results
• 1.3 Index figures
• 1.4 Performance metrics
• 1.5 Elapsed wall-clock time vs. CPU time
• 1.6 Resolution and precision
• 1.7 Synthetic benchmark
• 1.8 Application benchmark
• 1.9 Relevance

2. A variety of benchmarks

3. FPU tests: Whetstone and Sons, Ltd.

• 3.1 Whetstone history and general features
• 3.2 Getting the source and compiling it
• 3.3 Running Whetstone and gathering results
• 3.4 Examining the source code, the object code and interpreting the results

4. References

1. Basic concepts and definitions

1.1 Benchmark

A benchmark is a documented procedure that will measure the time needed by a computer system to execute a well-defined computing task. It is assumed that this time is related to the performance of the computer system and that someh ow the same procedure can be applied to other systems, so that comparisons can be made between different hardware/software configurations.

1.2 Benchmark results

From the definition of a benchmark, one can easily deduce that there are two basic procedures for benchmarking:

1. Measuring the time it takes for the system being examined to loop through a fixed number of iterations of a specific piece of code.
2. Measuring the number of iterations of a specific piece of code executed by the system under examination in a fixed amount of time.

If a single iteration of our test code takes a long time to execute, procedure 1 will be preferred. On the other hand, if the system being tested is able to execute thousands of iterations of our test code per second, procedure 2 should be chosen.

Both procedures 1 and 2 will yield final results in the form "seconds/iteration" or "iterations/second" (these two forms are interchangeable). One could imagine other algorithms, e.g. self-modifying code or measuring the time needed to reach a steady s tate of some sort, but this would increase the complexity of the code and produce results that would probably be next to impossible to analyze and compare.

1.3 Index figures

Sometimes, figures obtained from standard benchmarks on a system being tested are compared with the results obtained on a reference machine. The reference machine's results are called the baseline results. If we divide the results of the system under examination by the baseline results, we obtain a performance index. Obviously, the performance index for the reference machine is 1.0. An index has no units, it is just a relative measurement.

1.4 Performance metrics

The final result of any benchmarking procedure is always a set of numerical results which we can call speed or performance (for that particular aspect of our system effectively tested by the piece of code).

Under certain conditions we can combine results from similar tests or various indices into a single figure, and the term metric will be used to describe the "units" of performance for this benchmarking mix.

1.5 Elapsed wall-clock time vs. CPU time

Time measurements for benchmarking purposes are usually taken by defining a starting time and an ending time, the difference between the two being the elapsed wall-clock time. Wall-clock means we are not considering just CPU time, but the "real" time usually provided by an internal asynchronous real-time clock source in the computer or an external clock source (your wrist-watch for example). Some tests, however, make use of CPU time: the time effectively spent by the CPU of the system being test ed in running the specific benchmark, and not other OS routines.

1.6 Resolution and precision

Resolution and precision both measure the information provided by a data point, but should not be confused.

Resolution is the minimum time interval that can be (easily) measured on a given system. In Linux running on i386 architectures I believe this is 1/100 of a second, provided by the GNU C system library function times (see /usr/include/time .h - not very clear, BTW). Another term used with the same meaning is "granularity". David C. Niemi has developed an interesting technique to lower granularity to very low (sub-millisecond) levels on Linux systems, I hope he will contribute an explanation of his algorithm in the next article.

Precision is a measure of the total variability in the results for any given benchmark. Computers are deterministic systems and should always provide the same, identical benchmark results if running under identical conditions. However, since Linux is a multi-tasking, multi-user system, some tasks will be running in the background and will eventually influence the benchmark results.

This "random" error can be expressed as a time measurement (e.g. 20 seconds + or - 0.2 s) or as a percentage of the figure obtained by the benchmark considered (e.g. 20 seconds + or - 1%). Other terms sometimes used to describe variations in results ar e "variance", "noise", or "jitter".

Note that whereas resolution is system dependent, precision is a characteristic of each benchmark. Ideally, a well-designed benchmark will have a precision smaller than or equal to the resolution of the system being tested. It is very important to iden tify the sources of noise for any particular benchmark, since this provides an indication of possibly erroneous results.

1.7 Synthetic benchmark

A program or program suite specifically designed to measure the performance of a subsystem (hardware, software, or a combination of both). Whetstone is an example of a synthetic benchmark.

1.8 Application benchmark

A commonly executed application is chosen and the time to execute a given task with this application is used as a benchmark. Application benchmarks try to measure the performance of computer systems for some category of real-world computing task. Measu ring the time your Linux box takes to compile the kernel can be considered as a sort of application benchmark.

1.9 Relevance

A benchmark or its results are said to be irrelevant when they fail to effectively measure the performance characteristic the benchmark was designed for. Conversely, benchmark results are said to be relevant when they allow an accurate prediction of re al-life performance or meaningful comparisons between different systems.

2. A variety of benchmarks

The performance of a Linux system may be measured by all sorts of different benchmarks:

1. Kernel compilation performance.
2. FPU performance.
3. Integer math performance.
4. Memory access performance.
5. Disk I/O performance.
6. Ethernet I/O performance.
7. File I/O performance.
8. Web server performance.
9. Doom performance.
10. Quake performance.
11. X graphics performance.
12. 3D rendering performance.
13. SQL server performance.
14. Real-time performance.
15. Matrix performance.
16. Vector performance.
17. File server (NFS) performance.

Etc...

• Conclusion I: it's obvious that no single benchmark can provide results for all the above items.
• Conclusion II: you must first decide what you are trying to measure, then choose an appropriate benchmark (or write your own).
• Conclusion III: it's impossible to come up with a single figure (called Single Figure of Merit in benchmarking terminology) that will summarize the performance of a Linux system. Hence, no "Lhinuxstone" metric exists.
• Conclusion IV: benchmarking always takes more time than you thought it would.

3. FPU tests: Whetstone and Sons, Ltd.

Floating-point (FP) instructions are among the least used while running Linux. They probably represent < 0.001% of the instructions executed on an average Linux box, unless one deals with scientific computations. Besides, if you really want to know how well designed the FPU in your processor is, it's easier to have a look at its data sheet and check how many clock cycles it takes to execute a given FPU instruction. But there are more benchmarks that measure FPU performance than anything else. Why ?

1. RISC, pipelining, simultaneous issuing of instructions, speculative execution and various other CPU design tricks make the CPU performance, specially FPU performance, difficult to measure directly and simply. The execution time of an FPU instruction varies depending on the data, and a continuous stream of FPU instructions will execute under special circumstances that make direct predictions of performance impossible in most cases. Simulations (synthetic benchmarks) are needed.
2. FPU tests are easier to write than other benchmarks. Just put a bunch of FP instructions together and make a loop: voilà !
3. The Whetstone benchmark is widely (and freely) available in Basic, C and Fortran versions, in case you don't want to write your own FPU test.
4. FPU figures look good for marketing purposes. Here is what Dave Sill, the author of the comp.benchmarks FAQ, has to say about MFLOPS: "Millions of Floating Point Operations Per Second. Supposedly the rate at which the system can execute floating point instructions. Varies widely between different benchmarks and different configurations of the same benchmarks. Popular with marketing types because it's sounds like a "hard" value like miles per hour, and represents a simple concept."
5. If you are going to buy a Cray, you'd better have an excuse for it.
6. You can't get a data sheet for the Cray (or don't believe the numbers), but still want to know its FP performance.
7. You want to keep your CPU busy doing all sorts of useless FP calculations, and want to check that the chip gets very hot.
8. You want to discover the next big bug in the FPU of your processor, and get rich speculating with the manufacturer's shares.

Etc...

3.1 Whetstone history and general features

The original Whetstone benchmark was designed in the 60's by Brian Wichmann at the National Physical Laboratory, in England, as a test for an ALGOL 60 compiler for a hypothetical machine. The compilation system was named after the small town of Whetstone, where it was designed, and the name seems to have stuck to the benchmark itself.

The first practical implementation of the Whetstone benchmark was written by Harold Curnow in FORTRAN in 1972 (Curnow and Wichmann together published a paper on the Whetstone benchmark in 1976 for The Computer Journal). Historically it is the first major synthetic benchmark. It is designed to measure the execution speed of a variety of FP instructions (+, *, sin, cos, atan, sqrt, log, exp) on scalar and vector data, but also contains some integer code. Results are provided in MWIPS (Millions of Whetstone Instructions Per Second). The meaning of the expression "Whetstone Instructions" is not clear, though, at least after close examination of the C source code.

During the late 80's and early 90's it was recognized that Whetstone would not adequately measure the FP performance of parallel multiprocessor supercomputers (e.g. Cray and other mainframes dedicated to scientific computations). This spawned the development of various modern benchmarks, many of them with names like Fhoostone, as a humorous reference to Whetstone. Whetstone however is still widely used, because it provides a very reasonable metric as a measure of uniprocessor FP performance.

Whetstone has other interesting qualities for Linux users:

• Its source code is short and relatively easy to understand, with a clean, self-explanatory structure.
• The C version compiles cleanly on Linux boxes with gcc.
• Execution time is short: 100 seconds (by design).
• It is very precise (small variations in the results).
• CPU architecture digression: for the Whetstone benchmark, the object code that gets looped through is very small, fitting entirely in the L1 cache of most modern processors, hence keeping the FPU pipeline filled and the FPU permanently busy. This is desirable because Whetstone is doing exactly what we want it to do: measuring FPU performance, not CPU/L2 cache/main memory coupling, integer performance or any other feature of the system under test. Note however that has provided some conclusive evidence that at least some interaction with the L2 cache or main memory is taking place on Pentium (R) systems (Pentium CPUs have a sophisticated FPU instruction pipeline and can dispatch two FPU instructions on a single clock cycle. One pipe can execute all integer and FP instructions, while the other pipe can execute simple integer instructions and the FXCH FP instructions. This is quoted from Intel's datasheet on the Pentium processor, available at Intel's developers site). I wish somebody with a Pentium ICE equipment could investigate this a little further...

3.2 Getting the source and compiling it

Getting the standard C version by Roy Longbottom.

The version of the Whetstone benchmark that we are going to use for this example was slightly modified by Al Aburto and can be downloaded from his excellent FTP site dedicated to benchmarks. After downloading the file whets.c, you will have to edit slightly the source: a) Uncomment the "#define POSIX1" directive (this enables the Linux compatible timer routine). b) Uncomment the "#define DP" directive (since we are only interested in the Double Precision results).

Compiling

This benchmark is extremely sensitive to compiler optimization options. Here is the line I used to compile it: cc whets.c -o whets -O2 -fomit-frame-pointer -ffast-math -fforce-addr -fforce-mem -m486 -lm.

Note that some compiler options of some versions of gcc are buggy, most notably one of -O, -O2, -O3, ... together with -funroll-loops can cause gcc to emit incorrect code on a Linux box. You can test your gcc with a short test program available at Uwe Mayer's site. Of course, if your compiler is buggy, then any test results are not written in stone, to say the least (pun intended). In short, don't use -funroll-loops to compile this benchmark, and try to stick to the optimization options listed above.

3.3 Running Whetstone and gathering results

First runs

Just execute whets. Whetstone will display its results on standard output and also write a whets.res file if you give it the information it requests. Run it a few times to confirm that variations in the results are very small.

With L1, L2 or both L1 and L2 caches disabled

Some motherboards allow you to disable the L1 (internal) or L2 (external) caches through the BIOS configuration menus (take a look at the motherboard's manual; the ASUS P55T2P4 motherboard, for example, allows disabling both caches separately or together). You may want to experiment with these settings and/or main memory (DRAM) timing settings.

Without optimization

You can try to compile whets.c without any special optimization options, just to verify that compiler quality and compiler optimization options do influence benchmark results.

3.4 Examining the source code, the object code and interpreting the results

General program structure

The Whetstone benchmark main loop executes in a few milliseconds on an average modern machine, so its designers decided to provide a calibration procedure that will first execute 1 pass, then 5, then 25 passes, etc... until the calibration takes more than 2 seconds, and then guess a number of passes xtra that will result in an approximate running time of 100 seconds. It will then execute xtra passes of each one of the 8 sections of the main loop, measure the running time for each (for a total running time very near to 100 seconds) and calculate a rating in MWIPS, the Whetstone metric. This is an interesting variation in the two basic procedures described in Section 1.

Main loop

The main loop consists of 8 sections each containing a mix of various instructions representative of some type of computational task. Each section is itself a very short, very small loop, and has its own timing calculation. The code that gets looped through for section 8 for example is a single line of C code:

x = sqrt(exp(log(x)/t1); where x = 0.75 and t1=0.50000025, both defined as doubles.

Executable code size, library calls

Compiling as specified above with gcc 2.7.2.1, the resulting ELF executable whets is 13 096 bytes long on my system. It calls libc and of course libm for the trigonometric and transcendental math functions, but these should get compiled to very short executable code sequences since all modern CPUs have FPUs with these functions wired-in.

General comments

Now that we have an FPU performance figure for our machine, the next step is comparing it to other CPUs. Have you noticed all the data that whets.c asked you after you had run it for the first time? Well, Al Aburto has collected Whetstone results for your convenience at his site, you may want to download the data file and have a look at it. This kind of benchmarking data repository is very important, because it allows comparisons between various different machines. More on this topic in one of my next articles.

Whetstone is not a Linux specific test, it's not even an OS specific test, but it certainly is a good test for the FPU in your Linux box, and also gives an indication of compiler efficiency for specific kinds of applications that involve FP calculations.

I hope this gave you a taste of what benchmarking is all about.

4. References

Other references for benchmarking terminology:

• The comp.benchmarks FAQ by Dave Sill.
• The On-Line Computing Dictionary.
• The Linux Benchmarking HOWTO available from the LDP site and mirrors.

Copyright © 1997, André D. Balsa
Published in Issue 22 of the Linux Gazette, October 1997

"Linux Gazette...making Linux just a little more fun!"

One of the most common questions posted in the various Linux newsgroups is "Where can I find a good word-processor for Linux?". This question has several interesting ramifications:

• There is an unspoken assumption that a word processor is a vital application for an operating system.
• The query implies that the questioner has investigated the text processing capabilities readily available for Linux and has either found them too daunting to learn and/or not suited to the tasks at hand, or...
• The questioner is a recent migrant from one of the commercial OS's and is accustomed to a standard word processor.

A notion has become prevalent in the minds of many computer users these days: the idea that a complex word processor is the only tool suitable for creating text on a computer. I've talked with several people who think of an editor as a primitive relic of the bad old DOS days, a type of software which has been superseded by the modern word-processor. There is an element of truth to this, especially in a business environment in which even the simplest memos are distributed in one of several proprietary word-processor formats. But when it is unnecessary to use one of these formats, a good text editor has more power to manipulate text and is faster and more responsive.

The ASCII format, intended to be a universal means of representing and transferring text, does have several limitations. The fonts used are determined by the terminal type and capability rather than by the application, normally a fixed, monospace font. These limitations in one sense are virtues, though, as this least-common-denominator approach to representing text assures readability by everyone on all platforms. This is why ASCII is still the core format of e-mail and usenet messages, though there is a tendency in the large software firms to promote HTML as a replacement. Unfortunately, HTML can now be written so that it is essentially unreadable by anything other than a modern graphical browser. Of course, HTML is ASCII-based as well, but is meant to be interpreted or parsed rather than read directly.

Working with ASCII text directly has many advantages. The output is compact and easily stored, and separating the final formatting from actual writing allows the writer to focus on content rather than appearance. An ASCII document is not dependent on one application; the simplest of editors or even cat can access its content. There is an interesting parallel, perhaps coincidental, between the Unix use of ASCII and other OS's use of binary formats. All configuration files in a Linux or any Unix system are generally in plain ASCII format: compact,editable, and easily backed-up or transferred. Many programmers use Linux; source code is written in ASCII format, so perhaps using the format for other forms of text is a natural progression. The main configuration files for Win95, NT and OS/2 are in binary format, easily corruptible and not easily edited. Perhaps this is one reason users of these systems tend towards proprietary word-processing formats which, while not necessarily in binary format, aren't readable by ASCII-based editors or even other word-processors. But I digress...

There are several methods of producing professional-looking printable documents from ASCII input, the most popular being LaTeX, Lout, and Groff.

LaTeX, Leslie Lamport's macro package for the TeX low-level formatting system, is widely used in the academic world. It has become a standard, and has been refined to the point that bugs are rare. Its ability to represent mathematical equations is unparalleled, but this very fact has deterred some potential users. Mentioning LaTeX to people will often elicit a response such as: "Isn't that mainly used by scientists and mathematicians? I have no need to include equations in my writing, so why should I use it?" A full-featured word-processor (such as WordPerfect) also includes an equation editor, but (as with LaTeX) just because a feature exists doesn't mean you have to use it. LaTeX is well-suited to creating a wide variety of documents, from a simple business letter to articles, reports or full-length books. A wealth of documentation is available, including documents bundled with the distribution as well as those available on the internet. A good source is this ftp site, which is a mirror of CTAN, the largest on-line repository of TeX and LaTeX material.

LaTeX is easily installed from any Linux distribution, and in my experience works well "out of the box". Hardened LaTeX users type the formatting tagging directly, but there are several alternative approaches which can expedite the process, especially for novices. There is quite a learning curve involved in learning LaTeX from scratch, but using an intermediary interface will allow the immediate creation of usable documents by a beginner.

AucTeX is a package for either GNU Emacs or XEmacs which has a multitude of useful features helpful in writing LaTeX documents. Not only does the package provide hot-keys and menu-items for tags and environments, but it also allows easy movement through the document. You can run LaTeX or TeX interactively from Emacs, and even view the resulting output DVI file with xdvi. Emacs provides excellent syntax highlighting for LaTeX files, which greatly improves their readability. In effect AucTeX turns Emacs into a "front-end" for LaTeX. If you don't like the overhead incurred when running Emacs or especially XEmacs, John Davis' Jed and Xjed editors have a very functional LaTeX/TeX mode which is patterned after AucTeX. The console-mode Jed editor does syntax-highlighting of TeX files well without extensive fiddling with config files, which is rare in a console editor.

If you don't use Emacs or its variants there is a Tcl/Tk based front-end for LaTeX available called xtem. It can be set up to use any editor; the September 1996 issue of Linux Journal has a good introductory article on the package. Xtem has one feature which is useful for LaTeX beginners: on-line syntax help-files for the various LaTeX commands. The homepage for the package can be visited if you're interested.

It is fairly easy to produce documents if the default formats included with a TeX installation are used; more knowledge is needed to produce customized formats. Luckily TeX has a large base of users, many of whom have contributed a variety of style-formatting packages, some of which are included in the distribution, while others are freely available from TeX archive sites such as CTAN.

At a further remove from raw LaTeX is the LyX document processor. This program (still under development, but very usable) at first seems to be a WYSIWYG interface for LaTeX, but this isn't quite true. The text you type doesn't have visible LaTeX tagging, but it is formatted to fit the window on your screen which doesn't necessarily reflect the document's appearance when printed or viewed with GV or Ghostscript. In other words, the appearance of the text you type is just a user convenience. There are several things which can be done with a document typed in LyX. You can let LyX handle the entire LaTeX conversion process with a DVI or Postscript file as a result, which is similar to using a word-processor. I don't like to do it this way; one of the reasons I use Linux is because I'm interested in the underlying processes and how they work, and Linux is transparent. If I'm curious as to how something is happening in a Linux session I can satisfy that curiosity to whatever depth I like. Another option LyX offers is more to my taste: LyX can convert the document's format from the LaTeX-derived internal format to standard LaTeX, which is readable and can be loaded into an editor.

Load a LyX-created LaTeX file into an Emacs/Auctex session (if you have AucTeX set up right it will be called whenever a file with the .tex suffix is loaded), and your document will be displayed with new LaTeX tags interspersed throughout the text. The syntax-highlighting can make the text easier to read if you have font-locking set up to give a subdued color to the tagging (backslashes (\) and $ signs). This is an effective way to learn something about how LaTeX documents are written. Changes can be made from within the editor and you can let AucTeX call the LaTeX program to format the document, or you can continue with LyX. In effect this is using LyX as a preprocessor for AucTeX. This expands the user's options; if you are having trouble convincing LyX to do what you want, perhaps AucTeX can do it more easily.

Like many Linux software projects LyX is still in a state of flux. The release of beta version 0.12 is imminent; after that release the developers are planning to switch to another GUI toolkit (the current versions use the XForms toolkit). The 0.11.38 version I've been using has been working dependably for me (hint: if it won't compile, give the configure script the switch --disable-nls. This disables the internationalization support).

YODL (Yet One-Other Document Language) is another way of interacting with LaTeX. This system has a simplified tagging format which isn't hard to learn. The advantage of YODL is that from one set of marked-up source documents, output can be generated in LaTeX, HTML, and Groff man and ms formats. The package is well-documented. I wrote a short introduction to YODL in issue #9 of the Gazette. The current source for the package is this ftp site.

About thirteen years ago Jeffrey Kingston (of the University of Sydney, Australia) began to develop a document formatting system which became known as Lout. This system bears quite a bit of resemblance to LaTeX: it uses formatting tags (using the @ symbol rather than \) and its output is Postscript. Mr. Kingston calls Lout a high-level language with some similarities to Algol, and claims that user extensions and modifications are much easier to implement than in LaTeX. The package comes with hundreds of pages of Postscript documentation along with the Lout source files which were used to generate those book-length documents.

The Lout system is still maintained and developed, and in my trials seemed to work well, but there are some drawbacks. I'm sure Lout has nowhere near as many users as LaTeX. LaTeX is installed on enough machines that if you should want to e-mail a TeX file to someone (especially someone in academia) chances are that that person will have access to a machine with Tex installed and will be able to format and print or view it. LaTeX's large user-base also has resulted in a multitude of contributed formatting packages.

Another drawback (for me, at least) is the lack of available front-ends or editor-macro packages for Lout. I don't mind using markup languages if I can use, say, an Emacs mode with key-bindings and highlighting set up for the language. There may be such packages out there for Lout, but I haven't run across them.

Lout does have the advantage of being much more compact than a typical Tex installation. If you have little use for some of the more esoteric aspects of LaTeX, Lout might be just the thing. It can include tables, various types of lists, graphics, foot- and marginal notes, and equations in a document, and the Postscript output is the equal of what LaTeX generates.

Both RedHat and Debian have Lout packages available, and the source/documentation package is available from the Lout home FTP site.

Groff is an older system than TeX/LaTeX, dating back to the early days of unix. Often a first-time Linux user will neglect to install the Groff package, only to find that the man command won't work and that the man-pages are therefore inaccessible. As well as in day-to-day invocation by the man command, Groff is used in the publishing industry to produce books, though other formatting systems such as SGML are more common.

Groff is the epitome of the non-user-friendly and cryptic unix command-line tool. There are several man-pages covering various of Groff's components, but they seem to assume a level of prior knowledge without any hint as to where that knowledge might be acquired. I found them to be nearly incomprehensible. A search on the internet didn't turn up any introductory documents or tutorials, though there may be some out there. I suspect more complete documentation might be supplied with some of the commercial unix implementations; the original and now-proprietary version is called troff, and a later version is nroff; Groff is short for GNU roff.

Groff can generate Postscript, DVI, HP LaserJet4, and ASCII text formats.

Learning to use Groff on a Linux system might be an uphill battle, though Linux software developers must have learned enough of it at one time or other, as most programs come with Groff-tagged man-page files. Groff's apparent opacity and difficulty make LaTeX look easy in contrast!

Processing text with a mark-up language requires a different mode of thought concerning documents. On the one hand, writing blocks of ASCII is convenient and no thought needs to be given to the marking-up process until the end. A good editor provides so many features to deal with text that using any word-processor afterwards can feel constrictive. Many users, though, are attracted by the integration of functions in a word processor, using one application to produce a document without intermediary steps.

Though there are projects underway (such as Wurd) which may eventually result in a native Linux word-processor, there may be a reason why this type of application is still rare in the Linux world. Adapting oneself to Linux, or any unix-variant, is an adaptation to what has been called "the Unix philosophy", the practice of using several highly-refined and specific tools to accomplish a task, rather than one tool which tries to do it all. I get the impression that programmers attracted to free software projects prefer working on smaller specialized programs. As an example look at the plethora of mail- and news-readers available compared to the dearth of all-in-one internet applications. Linux itself is really just the kernel, which has attracted to itself all of the GNU and other software commonly distributed with it in the form of a distribution.

Christopher B. Browne has written an essay titled An Opinionated Rant About Word-Processors which deals with some of the issues discussed in this article; it's available at this site.

The StarOffice suite is an interesting case, one of the few instances of a large software firm (StarDivision) releasing a Linux version of an office productivity suite. The package has been available for some time now, first in several time-limited beta versions and now in a freely available release. It's a large download but it's also available on CDROM from Caldera. You would think that users would be flocking to it if the demand is really that high for such an application suite for Linux. Judging by the relatively sparse usenet postings I've seen, StarOffice hasn't exactly swept the Linux world by storm. I can think of a few possible reasons:

• Many hard-core Linux users aren't working in a corporate office setting in which such a product would be valuable; they are scientists, engineers or academics who are perfectly happy with LaTeX, Lout, Groff, et al.
• Then there are the users who have dual or multiple-boot set-ups; if they need to use MS Word they just boot from their Win95 or NT partitions.
• Another group of users run Linux at home and whatever OS their job requires at work.
• StarOffice is written with a cross-platform development tool-kit; this may be responsible for its bulk and lack of speed.

I remember the first time I started up the StarOffice word-processor. It was slow to load on a Pentium 120 with 32 mb. of RAM (and I thought XEmacs was slow!), and once the main window appeared it occurred to me that it just didn't look "at home" on a Linux desktop. All those icons and button-bars! It seemed to work well, but with the lack of English documentation (and not being able to convince it to print anything!) I eventually lost interest in using it. I realized that I prefer my familiar editors, and learning a little LaTeX seemed to be easier than trying to puzzle out the workings of an undocumented suite of programs. This may sound pretty negative, and I don't wish to denigrate the efforts of the StarDivision team responsible for the Linux porting project. If you're a StarOffice user happy with the suite (especially if you speak German and therefore can read the docs) and would like to present a dissenting view, write a piece on it for the Gazette!

Two other commercial word-processors for Linux are Applix and WordPerfect. Applix, available from RedHat, has received favorable reviews from many Linux users.

A company called SDCorp in Utah has ported Corel's WordPerfect 7 to Linux, and a (huge!) demo is available now from both the SDCorp ftp site and Corel's. Unfortunately both FTP servers are unable to resume interrupted downloads (usually indicating an NT server) so the CDROM version, available from the SDCorp website, is probably the way to go, if you'd like to try it out. The demo can be transformed into a registered program by paying for it, in which case a key is e-mailed to you which registers the program, but only for the machine it is installed on.

Addendum: I recently had an exchange of e-mail with Brad Caldwell, product manager for the SDCorp WordPerfect port. I complained about the difficulty of downloading the 36 mb. demo, and a couple of days later I was informed that the file has been split into nine parts, and that they were investigating the possibility of changing to an FTP server which supports interrupted downloads. The smaller files are available from this web page.

There exists a curious dichotomous attitude these days in the Linux community. I assume most people involved with Linux would like the operating system to gain more users and perhaps move a little closer to the mainstream. Linux advocates bemoan the relative lack of "productivity apps" for Linux, which would make the OS more acceptable in corporate or business environments. But how many of these advocates would use the applications if they were more common? Often the change of mindset discussed above mitigates against acceptance of Windows-like programs, with no source code available and limited access to the developers. Linux has strong roots in the GNU and free software movements (not always synonymous) and this background might be a barrier towards development of a thriving commercial software market.

"Linux Gazette...making Linux just a little more fun!"

Richard Stallman and the other members of the GNU Emacs development team are a rather reticent group of programmers. Unlike many other development projects in the free-software world, the Emacs beta program is restricted to a closed group of testers, and news of what progress is being made is scanty. In the past couple of months hints found in various usenet postings seemed to intimate that a new release of GNU Emacs was imminent, so every now and then I began to check the GNU main FTP site on the off-chance that a release had been made.

Early on the morning of September 17 I made a quick check before beginning my day's work, and there it was, a new Emacs 20.1 source archive. As with all Emacs source packages, it was large (over 13 megabytes) so I began the download with NcFtp and left it running.

There is always a delay between the release of a new version of a software package and the release of a Linux distribution's version, such as a Debian or RedHat binary package. Even if you usually use RPMs or *.deb releases (in many cases it's preferable) a source release of a major team-developed piece of software such as GNU Emacs will usually build easily on a reasonably up-to-date Linux machine. The included installation instructions are clear: just run the configure script, giving your machine-type and preferred installation directory as switches. In my case, this command did the trick:

./configure i586-Debian-linux-gnu --prefix=/mt

The script will generate a Makefile tailored to your machine; make, followed by make install and you're up and running.

It's been about a year since the last public GNU Emacs release, so there have been quite a few changes. One of the largest is the incorporation of the MULE (MUltiLingual Emacs) extensions, which give Emacs the capability of displaying extended character sets necessary for languages such as Chinese and Japanese. This won't be of interest to most English-speaking users, but if you're interested the necessary files are in a separate archive at the GNU site.

Here's a partial list of changes and updated packages:

• For some reason, the scroll-bar is now on the left, but it can be changed back to its old position on the right with the new Customize facility. Some day it would be nice if someone implemented a real scrollbar for GNU Emacs, with the usual buttons or arrows at top and bottom which allow smooth scrolling rather than paging, but it seems this is a low priority for the developers.
• Per Abrahamsen's Customize package is now thoroughly integrated with the majority of the included LISP packages, allowing easy customization of all sorts of options, with the results appended to your ~.emacs file. This so much easier than hacking on the .emacs file; I don't know how many times I've had a misplaced or unbalanced parentheses, causing Emacs to quit loading the file and giving me the dread message: Error in init file.
• Viper, CC-Mode, the GNUS newsreader, and many other extension packages have been updated.
• The default values for many configuration parameters have been changed to values more likely to be acceptable to most users, the sort of thing which would be entered in an ~/.emacs file.
• The syntax-highlighting color default values are now sensitive to whether you have a dark or light screen background; for the most part the dark-background default colors are readable, with enough contrast.
• The text-filling commands now handle indented and bulleted paragraphs more effectively.
• The word Emacs no longer is shown in the mode-line, allowing more room for line and column numbers, mode specifications, time of day, etc.
• For programmers, there are new commands for looking up symbols or files in the Info documentation files. As an example, in C mode the GNU libc Info files would be searched for a reference to the symbol or file at the cursor position in the current buffer.
• Another programmer's feature: Alt-tab (with a numeric argument) will now perform completion on a symbol name in the current buffer, using Info files as above.
• The main /lisp directory has been subdivided into several sub-directories, which makes individual files much easier to find.

Have you ever been puzzled or annoyed by the peculiar way the Emacs screen scrolls when using the up- or down- arrow keys? It's a jerky scroll, difficult for the eye to follow, which could only be partially alleviated by setting scroll-step to a small value. In 20.1 this has been changed, so that if you set scroll-step to 2 (setq scroll-step 2) the screen actually scrolls up and down smoothly, without the disorienting jerks. This feature alone makes the upgrade worthwhile!

Another Emacs quirk has been addressed with a new variable, scroll-preserve-screen-position. This variable, if set to t (which means "yes"), will allow the user to page-up and page-down and then returns the cursor to its original position when the starting page is shown again. I really like this. With the default behavior you have to find the cursor on the screen and manually move it back to where it was. This variable can be enabled with the line

(setq scroll-preserve-screen-position t)

entered into your ~.emacs init file.

What a labor-saver! Rather than searching for the documentation which deals with altering one of Emacs' default settings, the user is presented with a mouse-enabled screen from which changes can be made, either for the current session or permanently, in which case the changes are recorded in the user's ~.emacs file. It appears that a tremendous amount of work went into including the customization framework in the LISP files for Emacs' countless modes and add-on packages. A Customize screen can be summoned from the Help menu; the entries are in a cascading hierarchy, allowing an easy choice of the precise category a user might want to tweak. Here's a screenshot of a typical Customization screen:

Per Abrahamsen is to be congratulated for writing this useful utility, and for making it effective both for XEmacs and GNU Emacs users.

Emacs used to be thought of as a hefty, memory-intensive editor which tended to strain a computer's resources. Remember the old mock-acronym, Eight Megabytes And Constantly Swapping? These days it seems that the hardware has caught up with Emacs; today a mid-range machine can run Emacs easily, even with other applications running concurrently. Memory and hard-disk storage have become less expensive which makes Emacs usable for more people.

Some people are put off by the multiple keystrokes for even the most common commands. It's easy to rebind the keys, though. The function keys are handy, as they aren't in use by other Emacs commands. As examples, I have F1 bound to Kill-Buffer, F2 bound to Ispell-Word (which checks the spelling of the word under the cursor), F3 and F4 put the cursor at the beginning or end of the current file, and F7 is bound to Save-Buffer. Of course, these operations are on the menu-bar, but using the keyboard is quicker. If you are accustomed to a Vi-style editor, the Viper package allows toggling between the familiar Vi commands (which are extraordinarily quick, as most are a single keystroke) and the Emacs command set. This emulation mode has been extensively improved lately, and is well worth using.

Even with the exhaustively detailed Info files, the tutorial, etc. I would hesitate to recommend Emacs for a novice Linux user. There is enough to learn just becoming familiar with basic Linux commands without having to learn Emacs as well. I think Nedit would be a more appropriate choice for a new user familiar with Windows, OS/2, or the Macintosh, since its mouse-based operation and menu structure are reminiscent of editors from these operating systems.

Emacs has a way of growing on you; as your knowledge of its traits and capabilities increases the editor gradually is molded to your preferences and work habits. It is possible to use the editor at a basic level, (using just the essential commands), but it's a waste to run a large editor like Emacs without using at least some of its manifold capabilities.

"Linux Gazette...making Linux just a little more fun!"

Recently I happened across an ingeniously designed add-on LISP package for the GNU Emacs editor. It's called Notes-Mode, and it helps organize and cross-reference notes by subject and date. It was written by . Here's his account of how he happened to write the package:

Briefly, I started keeping notes on-line shortly after I got a portable computer in January, 1994. After a month-and-a-half of notes, I realized that one does not live by grep alone, so I started adding indexing facilities. In June of 1995 some other Ficus-project members started keeping and indexing on-line notes using other home-grown systems. After some discussion, we generalized my notes-mode work and they started using it. Over the next 18 months notes-mode grew. Finally, in April, 1996 I wrote documentation, guaranteeing that innovation on notes-mode will now cease or the documentation will become out of date.

Here's what one of my smaller notes files looks like:

25-Jul-97 Friday
----------------

* Today
-------
prev: <file:///~/notes/199707/970724#* Today>
next: <file:///~/notes/199707/970728#* Today>

* Prairie Plants
----------------
prev: <file:///~/notes/199707/970724#* Prairie Plants>
next: <none>

The first entry,Today, contains nothing; it just serves as a link to move from the current notes file to either the previous day's file or the next day's. Any other word preceded by an asterisk and a space will serve as a hyper-link to previous or next entries with the same subject. Type in a new (or previously-used) subject with the asterisk and space, press enter, and the dashed line and space will automatically be entered into the file; this format is what the Perl indexing script uses to identify discrete entries.

While in Emacs with a notes-mode file loaded, several keyboard commands allow you to navigate between successive entries, either by day or by subject, depending on where the cursor is when the keystroke is executed. A handy key-binding for notes-mode is Control-c n, which will initialize a new notes file for the day if the following LISP code is entered into your ~.emacs file:
(define-key global-map "^Cn" 'notes-index-todays-link). The "^C" part is entered into the file by entering Control-q Control-c.

When Notes-Mode is installed a subdirectory is created in your home directory called Notes. As you use the mode a subdirectory for each month is created as well as a subdirectory under each month's directory for each week in the month. The individual note files, one for each day the mode is used, are given numerical names; the format of the path and filename can be seen in the above example.

The ability to navigate among your notes is enabled by means of a Perl script called mkall, which is intended to be run daily by cron. Mkall in turn calls other Perl scripts which update the index file with entries for any new notes you may have made. This system works well, making good use of Linux's automation facilities. Once you have it set up you never have to think about it again.

While this mode is designed for an academic environment in which voluminous notes are taken on a variety of subjects, it can also be useful for anyone who wants to keep track of on-line notes. It could even be used as a means of organizing diary or journal entries. The only disadvantage I've seen is that, though the notes-files are ASCII text readable by any editor, the navigation and hyper-linking features are only available from within Emacs. This is fine if you use Emacs as your main editor but makes the package not too useful for anyone else. XEmacs users are out of luck as well, as the package doesn't work "out-of-the-box" with XEmacs. I imagine a skilled LISP hacker could modify Notes-Mode for XEmacs; I've made some tentative attempts but without success.

The only source I've seen for this package is from the author's web page, at this URL:
http://gost.isi.edu/~johnh/SOFTWARE/NOTES_MODE/index.html

The documentation for Notes-Mode can be browsed on-line at this site if you'd like to read more before trying it out.

"Linux Gazette...making Linux just a little more fun!"

Using m4 to write HTML.

By Bob Hepple

Contents:

• 1. Some limitations of HTML
• 2. Using m4
• 3. Examples of m4 macros
• 3.1 Sharing HTML elements across several page
• 3.2 Managing HTML elements that often change
• 3.3 Creating new text styles
• 3.4 Typing and mnemonic aids
• 3.5 Automatic numbering
• 3.6 Automatic date stamping
• 3.7 Generating Tables of Contents
• 3.7.1 Simple to understand TOC
• 3.7.2 Simple to use TOC
• 3.8 Simple tables
• 4. m4 gotchas
• 4.1 Gotcha 1 - quotes
• 4.2 Gotcha 2 - Word swallowing
• 4.3 Gotcha 3 - Comments
• 4.4 Gotcha 4 - Debugging
• 5. Conclusion
• 6. Files to download

1. Some limitations of HTML

I immediately turned to the WWW and looked up all sorts of tools - but quite honestly I was rather disappointed. Mostly, they were what I would call Typing Aids - instead of having to remember arcane incantations like <a href="link">text</a>, you are given a button or a magic keychord like ALT-CTRL-j which remembers the syntax and does all that nasty typing for you.

Linux to the rescue! HTML is built as ordinary text files and therefore the normal Linux text management tools can be used. This includes the revision control tools such as RCS and the text manipulation tools like awk, perl, etc. These offer significant help in version control and managing development by multiple users as well as in automating the process of extracting from a database and displaying the results (the classic "grep |sort |awk" pipeline).

The use of these tools with HTML is documented elsewhere, e.g. see Jim Weinrich's article in Linux Journal Issue 36, April 1997, "Using Perl to Check Web Links" which I'd highly recommend as yet another way to really flex those Linux muscles when writing HTML.

What I will cover here is a little work I've done recently with using m4 in maintaining HTML. The ideas can probably be extended to the more general SGML case very easily.

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2. Using m4

Instead of editing *.html files, I create *.m4 files with my favourite text editor. These look something like this:

m4_include(stdlib.m4)
_HEADER(`This is my header')
<P>This is some plain text<P>
_HEAD1(`This is a main heading')
<P>This is some more plain text<P>
_TRAILER

The format is simple - just HTML code but you can now include files and add macros rather like in C. I use a convention that my new macros are in capitals and start with "_" to make them stand out from HTML language and to avoid name-space collisions.

The m4 file is then processed as follows to create an .html file e.g.

m4 -P <file.m4 >file.html

This is especially easy if you create a "makefile" to automate this in the usual way. Something like:

.SUFFIXES: .m4 .html
.m4.html:
        m4 -P $*.m4 >$*.html
default: index.html
*.html: stdlib.m4
all: default PROJECT1 PROJECT2
PROJECT1:
        (cd project2; make all)
PROJECT2:
        (cd project2; make all)

The most useful commands in m4 include the following which are very similar to the cpp equivalents (shown in brackets):

m4_include:

includes a common file into your HTML (#include)

m4_define:

defines an m4 variable (#define)

m4_ifdef:

a conditional (#ifdef)

Some other commands which are useful are:

m4_changecom:

change the m4 comment character (normally #)

m4_debugmode:

control error disgnostics

m4_traceon/off:

turn tracing on and off

m4_dnl:

comment

m4_incr, m4_decr:

simple arithmetic

m4_eval:

more general arithmetic

m4_esyscmd:

execute a Linux command and use the output

m4_divert(i):

This is a little complicated, so skip on first reading. It is a way of storing text for output at the end of normal processing - it will come in useful later, when we get to automatic numbering of headings. It sends output from m4 to a temporary file number i. At the end of processing, any text which was diverted is then output, in the order of the file number i. File number -1 is the bit bucket and can be used to comment out chunks of comments. File number 0 is the normal output stream. Thus, for example, you can `m4_divert' text to file 1 and it will only be output at the end.

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3. Examples of m4 macros

3.1 Sharing HTML elements across several page

In many "nests" of HTML pages, each page shares elements such as a button bar like this:

[Home] [Next] [Prev] [Index]

This is fairly easy to create in each page - the trouble is that if you make a change in the "standard" button-bar then you then have the tedious job of finding each occurance of it in every file and then manually make the changes.

With m4 we can more easily do this by putting the shared elements into an m4_include statement, just like C.

While I'm at it, I might as well also automate the naming of pages, perhaps by putting the following into an include file, say "button_bar.m4":

m4_define(`_BUTTON_BAR', 
        <a href="homepage.html">[Home]</a>
        <a href="$1">[Next]</a>
        <a href="$2">[Prev]</a>
        <a href="indexpage.html">[Index]</a>)

and then in the document itself:

m4_include button_bar.m4
_BUTTON_BAR(`page_after_this.html', 
        `page_before_this.html')

The $1 and $2 parameters in the macro definition are replaced by the strings in the macro call.

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3.2 Managing HTML elements that often change

It is very troublesome to have items change in multiple HTML pages. For example, if your email address changes then you will need to change all references to the new address. Instead, with m4 you can do something like this in your stdlib.m4 file:

m4_define(`_EMAIL_ADDRESS', `[email protected]')

and then just put _EMAIL_ADDRESS in your m4 files.

A more substantial example comes from building strings up with multiple components, any of which may change as the page is developed. If, like me, you develop on one machine, test out the page and then upload to another machine with a totally different address then you could use the m4_ifdef command in your stdlib.m4 file (just like the #ifdef command in cpp):

m4_define(`_LOCAL')
.
.
m4_define(`_HOMEPAGE', 
        m4_ifdef(`_LOCAL', `//127.0.0.1/~YourAccount', 
                `http://ISP.com/~YourAccount'))

m4_define(`_PLUG', `<A REF="http://www.ssc.com/linux/">
        <IMG SRC="_HOMEPAGE/gif/powered.gif" 
        ALT="[Linux Information]"> </A>')

Note the careful use of quotes to prevent the variable _LOCAL from being expanded. _HOMEPAGE takes on different values according to whether the variable _LOCAL is defined or not. This can then ripple through the entire project as you make the pages.

In this example, _PLUG is a macro to advertise Linux. When you are testing your pages, you use the local version of _HOMEPAGE. When you are ready to upload, you can remove or comment out the _LOCAL definition like this:

m4_dnl m4_define(`_LOCAL')

... and then re-make.

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3.3 Creating new text styles

m4_define(`_MYQUOTE',
        <BLOCKQUOTE><EM>$1</EM></BLOCKQUOTE>)

If, later, you decide you prefer <STRONG> instead of <EM> it is a simple matter to change the definition and then every _MYQUOTE paragraph falls into line with a quick make.

The classic guides to good HTML writing say things like "It is strongly recommended that you employ the logical styles such as <EM>...</EM> rather than the physical styles such as <I>...</I> in your documents." Curiously, the WYSIWYG editors for HTML generate purely physical styles. Using these m4 styles may be a good way to keep on using logical styles.

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3.4 Typing and mnemonic aids

I don't depend on WYSIWYG editing (having been brought up on troff) but all the same I'm not averse to using help where it's available. There is a choice (and maybe it's a fine line) to be made between:

<BLOCKQUOTE><PRE><CODE>Some code you want to display.
</CODE></PRE></BLOCKQUOTE>

and:

_CODE(Some code you want to display.)

In this case, you would define _CODE like this:

m4_define(`_CODE',
         <BLOCKQUOTE><PRE><CODE>$1</CODE></PRE></BLOCKQUOTE>)

Which version you prefer is a matter of taste and convenience although the m4 macro certainly saves some typing and ensures that HTML codes are not interleaved. Another example I like to use (I can never remember the syntax for links) is:

m4_define(`_LINK', <a href="$1">$2</a>)

Then,

<a href="URL_TO_SOMEWHERE">Click here to get to SOMEWHERE </a>

becomes:

_LINK(`URL_TO_SOMEWHERE', `Click here to get to SOMEWHERE')

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3.5 Automatic numbering

m4 has a simple arithmetic facility with two operators m4_incr and m4_decr which act as you might expect - this can be used to create automatic numbering, perhaps for headings, e.g.:

m4_define(_CARDINAL,0)

m4_define(_H, `m4_define(`_CARDINAL',
        m4_incr(_CARDINAL))<H2>_CARDINAL.0 $1</H2>')

_H(First Heading)
_H(Second Heading)

This produces:

<H2>1.0 First Heading</H2>
<H2>2.0 Second Heading</H2>

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3.6 Automatic date stamping

This page was updated on m4_esyscmd(date)

which produces:

This page was last updated on Fri May 9 10:35:03 HKT 1997

Of course, you could also use the date, revision and other facilities of revision control systems like RCS or SCCS, e.g. $Date$.

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3.7 Generating Tables of Contents

Using m4 allows you to define commonly repeated phrases and use them consistently - I hate repeating myself because I am lazy and because I make mistakes, so I find this feature absolutely key.

A good example of the power of m4 is in building a table of contents in a big page (like this one). This involves repeating the heading title in the table of contents and then in the text itself. This is tedious and error-prone especially when you change the titles. There are specialised tools for generating tables of contents from HTML pages but the simple facility provided by m4 is irresistable to me.

3.7.1 Simple to understand TOC

The following example is a fairly simple-minded Table of Contents generator. First, create some useful macros in stdlib.m4:

m4_define(`_LINK_TO_LABEL', <A HREF="#$1">$1</A>)
m4_define(`_SECTION_HEADER', <A NAME="$1"><H2>$1</H2></A>)

Then define all the section headings in a table at the start of the page body:

m4_define(`_DIFFICULTIES', `The difficulties of HTML')
m4_define(`_USING_M4', `Using <EM>m4</EM>')
m4_define(`_SHARING', `Sharing HTML Elements Across Several Pages')

Then build the table:

<UL><P>
        <LI> _LINK_TO_LABEL(_DIFFICULTIES)
        <LI> _LINK_TO_LABEL(_USING_M4)
        <LI> _LINK_TO_LABEL(_SHARING)
<UL>

Finally, write the text:

.
.
_SECTION_HEADER(_DIFFICULTIES)
.
.

The advantages of this approach are that if you change your headings you only need to change them in one place and the table of contents is automatically regenerated; also the links are guaranteed to work.

Hopefully, that simple version was fairly easy to understand.

Contents

3.7.2 Simple to use TOC

The Table of Contents generator that I normally use is a bit more complex and will require a little more study, but is much easier to use. It not only builds the Table, but it also automatically numbers the headings on the fly - up to 4 levels of numbering (e.g. section 3.2.1.3 - although this can be easily extended). It is very simple to use as follows:

1. Where you want the table to appear, call Start_TOC
2. at every heading use _H1(`Heading for level 1') or _H2(`Heading for level 2') as appropriate.
3. After the very last HTML code (probably after </HTML>), call End_TOC
4. and that's all!

The code for these macros is a little complex, so hold your breath:

m4_define(_Start_TOC,`<UL><P>m4_divert(-1)
  m4_define(`_H1_num',0)
  m4_define(`_H2_num',0)
  m4_define(`_H3_num',0)
  m4_define(`_H4_num',0)
  m4_divert(1)')

m4_define(_H1, `m4_divert(-1)
  m4_define(`_H1_num',m4_incr(_H1_num))
  m4_define(`_H2_num',0)
  m4_define(`_H3_num',0)
  m4_define(`_H4_num',0)
  m4_define(`_TOC_label',`_H1_num. $1')
  m4_divert(0)<LI><A HREF="#_TOC_label">_TOC_label</A>
  m4_divert(1)<A NAME="_TOC_label">
        <H2>_TOC_label</H2></A>')
.
.
[definitions for _H2, _H3 and _H4 are similar and are 
in the downloadable version of stdlib.m4]
.
.

m4_define(_End_TOC,`m4_divert(0)</UL><P>')

One restriction is that you should not use diversions within your text, unless you preserve the diversion to file 1 used by this TOC generator.

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3.8 Simple tables

Other than Tables of Contents, many browsers support tabular information. Here are some funky macros as a short cut to producing these tables. First, an example of their use:

<CENTER>
_Start_Table(BORDER=5)
_Table_Hdr(,Apples, Oranges, Lemons)
_Table_Row(England,100,250,300)
_Table_Row(France,200,500,100)
_Table_Row(Germany,500,50,90)
_Table_Row(Spain,,23,2444)
_Table_Row(Denmark,,,20)
_End_Table
</CENTER>

...and now the code. Note that this example utilises m4's ability to recurse:

m4_dnl _Start_Table(Columns,TABLE parameters)
m4_dnl defaults are BORDER=1 CELLPADDING="1" CELLSPACING="1"
m4_dnl WIDTH="n" pixels or "n%" of screen width
m4_define(_Start_Table,`<TABLE $1>')

m4_define(`_Table_Hdr_Item', `<th>$1</th>
  m4_ifelse($#,1,,`_Table_Hdr_Item(m4_shift($@))')')

m4_define(`_Table_Row_Item', `<td>$1</td>
  m4_ifelse($#,1,,`_Table_Row_Item(m4_shift($@))')')

m4_define(`_Table_Hdr',`<tr>_Table_Hdr_Item($@)</tr>')
m4_define(`_Table_Row',`<tr>_Table_Row_Item($@)</tr>')

m4_define(`_End_Table',</TABLE>)

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4. m4 gotchas

Unfortunately, m4 is not unremitting sweetness and light - it needs some taming and a little time spent on familiarisation will pay dividends. Definitive documentation is available (for example in emacs' info documentation system) but, without being a complete tutorial, here are a few tips based on my fiddling about with the thing.

4.1 Gotcha 1 - quotes

m4's quotation characters are the grave accent ` which starts the quote, and the acute accent ' which ends it. It may help to put all arguments to macros in quotes, e.g.

_HEAD1(`This is a heading')

The main reason for this is in case there are commas in an argument to a macro - m4 uses commas to separate macro parameters, e.g. _CODE(foo, bar) would print the foo but not the bar. _CODE(`foo, bar') works properly.

This becomes a little complicated when you nest macro calls as in the m4 source code for the examples in this paper - but that is rather an extreme case and normally you would not have to stoop to that level.

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4.2 Gotcha 2 - Word swallowing

The worst problem with m4 is that some versions of it "swallow" key words that it recognises, such as "include", "format", "divert", "file", "gnu", "line", "regexp", "shift", "unix", "builtin" and "define". You can protect these words by putting them in m4 quotes, for example:

Smart people `include' Linux in their list
of computer essentials.

The trouble is, this is a royal pain to do - and you're likely to forget which words need protecting.

Another, safer way to protect keywords (my preference) is to invoke m4 with the -P or --prefix-builtins option. Then, all builtin macro names are modified so they all start with the prefix m4_ and ordinary words are left alone. For example, using this option, one should write m4_define instead of define (as shown in the examples in this article).

The only trouble is that not all versions of m4 support this option - notably some PC versions under M$-DOS. Maybe that's just another reason to steer clear of hack code on M$-DOS and stay with Linux!

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4.3 Gotcha 3 - Comments

Comments in m4 are introduced with the # character - everything from the # to the end of the line is ignored by m4 and simply passed unchanged to the output. If you want to use # in the HTML page then you would need to quote it like this - `#'. Another option (my preference) is to change the m4 comment character to something exotic like this: m4_changecom(`[[[[') and not have to worry about `#' symbols in your text.

If you want to use comments in the m4 file which do not appear in the final HTML file, then the macro m4_dnl (dnl = Delete to New Line) is for you. This suppresses everything until the next newline.

m4_define(_NEWMACRO, `foo bar') m4_dnl This is a comment

Yet another way to have source code ignored is the m4_divert command. The main purpose of m4_divert is to save text in a temporary buffer for inclusion in the file later on - for example, in building a table of contents or index. However, if you divert to "-1" it just goes to limbo-land. This is useful for getting rid of the whitespace generated by the m4_define command, e.g.:

m4_divert(-1) diversion on
m4_define(this ...)
m4_define(that ...)
m4_divert       diversion turned off

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4.4 Gotcha 4 - Debugging

Another tip for when things go wrong is to increase the amount of error diagnostics that m4 emits. The easiest way to do this is to add the following to your m4 file as debugging commands:

m4_debugmode(e)
m4_traceon
.
.
buggy lines
.
.
m4_traceoff

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5. Conclusion

<!--#include file="junk.html" -->

The problem is that:

• The work of including and interpreting the include is done on the server-side before downloading and adds a big overhead as the server has to scan files for `include' statements.
• Consequently most servers (especially public ISP's) deactivate this feature.
• `include' is all you get - no macro substitution, no parameters to macros, no ifdef, etc, etc.

There are several other features of m4 that I have not yet exploited in my HTML ramblings so far, such as regular expressions and doubtless many others. It might be interesting to create a "standard" stdlib.m4 for general use with nice macros for general text processing and HTML functions. By all means download my version of stdlib.m4 as a base for your own hacking. I would be interested in hearing of useful macros and if there is enough interest, maybe a Mini-HOWTO could evolve from this paper.

There are many additional advantages in using Linux to develop HTML pages, far beyond the simple assistance given by the typical Typing Aids and WYSIWYG tools.

Certainly, this little hacker will go on using m4 until HTML catches up - I will then do my last make and drop back to using pure HTML.

I hope you enjoy these little tricks and encourage you to contribute your own. Happy hacking!

6. Files to download

using_m4.html        :this file
using_m4.m4     :m4 source
stdlib.m4 :Include file
makefile

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"Linux Gazette...making Linux just a little more fun!"

An introduction to The Connecticut Free Unix Group

by Lou Rinaldi , CFUG Co-Founder

October of 1996 was when Nate Smith and I first began discussing the creation of a local-area unix users' group here in Connecticut, something we felt the area was desperately in need of. We bantered around some initial ideas; some great, some not so great. Finally we decided on creating a group whose focus was on the "free unix" community. CFUG, The Connecticut Free Unix Group, was born in November of 1996. Both of us had very busy schedules, so all of the time we were going to invest in this project came directly from our ever-decreasing periods of leisure activity. We agreed upon three major goals for CFUG: The first was the wide distribution and implementation of free, unix-like operating systems and software. The second was educating the public about important developments in the evolution of free operating systems. Finally, we strove to provide an open, public forum for debate and discussion about issues related to these topics. After writing to several major vendors and asking for donations of their surplus stock and/or older software releases, the packages began rolling in. (After all, we wanted to create some sort of incentive for people to come to the first meeting)! We then got started doing some heavy advertising on the newsgroups, in local computer stores and also on local college campuses. Finally, after securing an honored guest speaker for our first meeting, (Lar Kaufman, co-author of the seminal reference book "Running Linux"), we were ready to set a date. December 9th, 1996 marked the first official CFUG gathering, which took place at a local public library. We've held meetings on the second Monday of each month ever since, and are now widely recognized as Connecticut's only organization dedicated to the entire free unix community. We've since lost Nate Smith to the lucrative wiles of Silicon Valley, but we continue to carry on with our original goals. We have close relations with companies such as Caldera Inc., InfoMagic Inc., and Red Hat Software, as well as such non-commercial entities as The FreeBSD Project, Software In The Public Interest (producers of Debian GNU/Linux), The OpenBSD Project and The Free Software Foundation. We were also featured on the front page of the Meriden Record-Journal, a major local newspaper, on May 26th of this year. Our future plans include more guest speakers, as well as trips to events of pertinence throughout New England.

For more information, please check our website - http://www.cfug.org

There is a one-way mailing list for announcements concerning CFUG. You can sign up by emailing with "subscribe" as the first line of the message body (without the quotes).

"Linux Gazette...making Linux just a little more fun!"

Review: The Unix-Hater's Handbook

by Andrew Kuchling

I've written a review of an old (1994-vintage) book that may be of interest to Linuxers. While even just its title will annoy people, there actually is material of interest in the book to Linux developers and proponents.

Andrew Kuchling
[email protected]
http://starship.skyport.net/crew/amk/

Summary: A sometimes enraging book for a Linux fan, but there are valuable insights lurking here.

In his Anti-Forward to this book, Dennis Ritchie writes "You claim to seek progress, but you succeed mainly in whining." That's a pretty accurate assessment of this book; it's one long complaint about work lost due to crashes, time wasted finding workarounds for bugs, unclear documentation, and obscure command-line arguments. Similar books could be written about any operating system. Obviously, I don't really agree with this book; I wouldn't be using Linux if I did. However, there is informative material here for people interested in Linux development, so it's worth some attention.

The book describes problems and annoyances with Unix; since it was inspired by a famous mailing list called UNIX-HATERS, there are lots of real-life horror stores, some hilarious and some wrenching. The shortcomings described here obviously exist, but in quite a few cases the problem has been fixed, or rendered irrelevant, by further development. Two examples:

* On the Unix file system: "...since most disk drives can transfer up to 64K bytes in a single burst, advanced file systems store files in contiguous blocks so they can be read and written in a single operation ... All of these features have been built and fielded in commercially offered operating systems. Unix offers none of them." But the ext2 file system, used on most Linux systems, does do this; there's nothing preventing the implementation of better filesystems.

* "Unix offers no built-in system for automatically encrypting files stored on the hard disk." (Do you know of any operating system that has such capability out of the box? Can you imagine the complaints from users who forget their passwords?) Anyway, software has been written to do this, either as an encrypting NFS server (CFS) or as a kernel module (the loopback device).

There are some conclusions that I draw from reading this book:

First, when the book was written in 1994, the free Unixes weren't very well known, so the systems described are mostly commercial ones. Proponents of free software should notice how many of the problems stem from the proprietary nature of most Unix variants at the time of writing. The authors point out various bugs and missing features in shells and utilities, flaws which could be *fixed* if the source code was available.

Better solutions sometimes didn't become popular, because they were owned by companies with no interest in sharing the code. For example, the book praises journalled file systems such as the Veritas file system, because they provide faster operation, and are less likely to lose data when the computer crashes. The authors write, "Will journaling become prevalent in the Unix world at large? Probably not. After all, it's nonstandard." More importantly, I think, the file system was proprietary software, and companies tend to either keep the code secret (to preserve their competitive advantage), or charge large fees to license the code (to improve their balance sheets).

The chapter on the X Window System is devastating and accurate; X really is an overcomplicated system, and its division between client and server isn't always optimal. An interesting solution is suggested; let programs extend the graphics server by sending it code. This approach was used by Sun's NeWS system, which used PostScript as the language. Unfortunately NeWS is now quite dead; it was a proprietary system, after all, and was killed off by X, which was freely available from MIT. (Trivia: NeWS was designed by James Gosling, who is now well-known for designing Java. Sun seems determined not to make the same mistake with Java... we hope.)

Second, many of the problems can be fixed by integrating better tools into the system. The Unix 'find' command has various problems which are described in chapter 8 of the book, and are pretty accurate, though they seem to have been fixed in GNU find. Someone has also written GNU locate, an easier way to find files. It runs a script nightly to build a database of filenames, and the 'locate' command searches through that database for matching files. You could make this database more than just a list of filenames; add the file's size and creation time, and you can do searches on those fields. One could envision a daemon which kept the database instantly up to date with kernel assistance. The source is available, so the idea only needs an author to implement it...

Chapter 8 also points out that shell programming is complex and limited; shell scripts depend on subprograms like 'ls' which differ from system to system, making portability a problem, and the quoting rules are elaborate and difficult to apply recursively. This is true, and is probably why few really sizable shell scripts are written today; instead, people use scripting language like Perl or Python, which are more powerful and easier to use.

Most important for Linux partisans, though, it's very important to note that not all of the flaws described have been fixed in Linux yet! For example, most Linux distributions don't really allow you to undelete files, though the Midnight Commander program apparently supports undeletes. As the authors say, 'sendmail' really is very buggy, and Unix's security model isn't very powerful. But people are working on new programs that do sendmail's job, and they're coding security features like the immutable attributes, and debating new security schemes.

For this reason, the book is very valuable as a pointer to things which still need fixing. I'd encourage Linux developers, or people looking for a Linux project, to read this book. Your blood pressure might soar as you read it, but look carefully at each complaint and ask "Is this complaint really a problem? If yes, how could it be fixed, and the system improved? Could I implement that improvement?"

Contents:

• About This Month's Authors
• Not Linux

Larry Ayers

Jim Dennis

John M. Fisk

Michael J. Hammel

Bob Hepple

Thanks to everyone who contributed to this month's issue!

I'm very excited to edit the Linux Gazette for October.
At my last job, where I fixed computers for a big company, I was talking with a woman about life in general while fixing her computer, and suddenly she blurted: "Oh my God! You're really a computer geek!" She immediately apologized and explained that she didn't mean any offense, even though I had a huge smile on my face and was trying to explain that I appreciated the compliment.

After many experiences like that, working with SSC has been a welcome change. And since Linux Gazette is one of the places where geeks come home to roost, I'm happy to be a part of it.

I just came back from the Grace Hopper Celebration for Women in Computing, which was held in San Jose, California this year. To quote Bill and Ted, it was totally awesome! I got to meet the illustrious Anita Borg, the amazing Ruzena Bajcny, and the inspiring Fran Allen from IBM, as well as many many many others who came from all over the country, and from dozens of countries from around the world. It was the most incredible even that I have ever attended, and I encourage everyone to go to the next one which will be in the year 2000.

Margie Richardson will return next month as Editor-In-Chief, and I'll be helping out on the sidelines. I'm really glad that I got the chance to be the Big Cheese for a month. :)
Keep sending those articles to !

Until next month, keep reading and keep hacking!

Viktorie Navratilova
Editor, Linux Gazette

Linux Gazette Issue 22, October 1997, http://www.ssc.com/lg/
This page written and maintained by the Editor of Linux Gazette,