Rename configure.in to configure.ac

This is the preferred filename to use with Autoconf 2.50 and later.

acinclude.m4

@@ -1,4 +1,4 @@
-dnl Helper macros for Tor configure.in
+dnl Helper macros for Tor configure.ac
 dnl Copyright (c) 2001-2004, Roger Dingledine
 dnl Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson
 dnl Copyright (c) 2007-2008, Roger Dingledine, Nick Mathewson

contrib/updateVersions.pl

@@ -1,6 +1,6 @@
 #!/usr/bin/perl -w
 
-$CONFIGURE_IN = './configure.in';
+$CONFIGURE_IN = './configure.ac';
 $ORCONFIG_H = './src/win32/orconfig.h';
 $TOR_NSI = './contrib/tor-mingw.nsi.in';
 
@@ -13,7 +13,7 @@ demand($CONFIGURE_IN);
 demand($ORCONFIG_H);
 demand($TOR_NSI);
 
-# extract version from configure.in
+# extract version from configure.ac
 
 open(F, $CONFIGURE_IN) or die "$!";
 $version = undef;

doc/HACKING

@@ -467,7 +467,7 @@ a stable release, add it to the ReleaseNotes file too. If we're adding
 to a release-0.2.x branch, manually commit the changelogs to the later
 git branches too.
 
-4) Bump the version number in configure.in and rebuild.
+4) Bump the version number in configure.ac and rebuild.
 
 5) Make dist, put the tarball up somewhere, and tell #tor about it. Wait
 a while to see if anybody has problems building it. Try to get Sebastian

src/common/compat.c

@@ -18,7 +18,7 @@
 /* XXXX024 We should just  use AC_USE_SYSTEM_EXTENSIONS in our autoconf,
  * and get this (and other important stuff!) automatically. Once we do that,
  * make sure to also change the extern char **environ detection in
- * configure.in, because whether that is declared or not depends on whether
+ * configure.ac, because whether that is declared or not depends on whether
  * we have _GNU_SOURCE defined! Maybe that means that once we take this out,
  * we can also take out the configure check. */
 #define _GNU_SOURCE