The Autoconf package contains the autoconf, autoheader, autoreconf, autoscan, autoupdate and ifnames programs
Autoconf is a tool for producing shell scripts that automatically configure software source code packages to adapt to many kinds of UNIX-like systems. The configuration scripts produced by Autoconf are independent of Autoconf when they are run, so their users do not need to have Autoconf.
The autoheader program can create a template file of C #define statements for configure to use
If there are a lot of Autoconf-generated configure scripts, the autoreconf program can save some work. It runs autoconf (and autoheader, where appropriate) repeatedly to remake the Autoconf configure scripts and configuration header templates in the directory tree rooted at the current directory.
The autoscan program can help to create a configure.in file for a software package. autoscan examines source files in the directory tree rooted at a directory given as a command line argument, or the current directory if none is given. It searches the source files for common portability problems and creates a file configure.scan which is a preliminary configure.in for that package.
The autoupdate program updates a configure.in file that calls Autoconf macros by their old names to use the current macro names.
ifnames can help when writing a configure.in for a software package. It prints the identifiers that the package already uses in C preprocessor conditionals. If a package has already been set up to have some portability, this program can help to figure out what its configure needs to check for. It may help fill in some gaps in a configure.in generated by autoscan.