configure.inAutomake scans the package's configure.in to determine certain
information about the package. Some autoconf macros are required
and some variables must be defined in configure.in. Automake
will also use information from configure.in to further tailor its
output.
Automake also supplies some Autoconf macros to make the maintenance
easier. These macros can automatically be put into your
aclocal.m4 using the aclocal program.