From 4e569696da42ded9ac772cf76e998066a069c5ae Mon Sep 17 00:00:00 2001
From: Glenn Morris <rgm@gnu.org>
Date: Sun, 9 May 2010 17:11:40 -0700
Subject: [PATCH] Regenerate configure, src/config.in.

---
 configure     | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 src/config.in |  6 ++++++
 2 files changed, 57 insertions(+)

diff --git a/configure b/configure
index 2a9c466400c..27216cb8222 100755
--- a/configure
+++ b/configure
@@ -755,6 +755,7 @@ LIBXSM
 ALLOCA
 liblockfile
 LIBS_MAIL
+BLESSMAIL_TARGET
 LIBOBJS
 NEED_SETGID
 KMEM_GROUP
@@ -17565,6 +17566,56 @@ done
 
 
 
+## Define MAIL_USE_FLOCK (or LOCKF) if the mailer uses flock (or lockf) to
+## interlock access to the mail spool.  The alternative is a lock file named
+## /usr/spool/mail/$USER.lock.
+mail_lock=no
+case "$opsys" in
+  aix4-2) mail_lock="lockf" ;;
+
+  gnu|freebsd|netbsd|openbsd|darwin|irix6-5) mail_lock="flock" ;;
+
+  ## On GNU/Linux systems, both methods are used by various mail programs.
+  ## I assume most people are using newer mailers that have heard of flock.
+  ## Change this if you need to.
+  ## Debian contains a patch which says: ``On Debian/GNU/Linux systems,
+  ## configure gets the right answers, and that means *NOT* using flock.
+  ## Using flock is guaranteed to be the wrong thing. See Debian Policy
+  ## for details.'' and then uses `#ifdef DEBIAN'.  Unfortunately the
+  ## Debian maintainer hasn't provided a clean fix for Emacs.
+  ## movemail.c will use `maillock' when MAILDIR, HAVE_LIBMAIL and
+  ## HAVE_MAILLOCK_H are defined, so the following appears to be the
+  ## correct logic.  -- fx
+  ## We must check for HAVE_LIBLOCKFILE too, as movemail does.
+  ## liblockfile is a Free Software replacement for libmail, used on
+  ## Debian systems and elsewhere. -rfr.
+  gnu-*)
+    mail_lock="flock"
+    if test $have_mail = yes || test $have_lockfile = yes; then
+      test $ac_cv_header_maillock_h = yes && mail_lock=no
+    fi
+    ;;
+esac
+
+BLESSMAIL_TARGET=
+case "$mail_lock" in
+  flock)
+cat >>confdefs.h <<\_ACEOF
+#define MAIL_USE_FLOCK 1
+_ACEOF
+ ;;
+
+  lockf)
+cat >>confdefs.h <<\_ACEOF
+#define MAIL_USE_LOCKF 1
+_ACEOF
+ ;;
+
+  *) BLESSMAIL_TARGET="need-blessmail" ;;
+esac
+
+
+
 
 
 
diff --git a/src/config.in b/src/config.in
index d9c80c8faaf..5fb0cd7d569 100644
--- a/src/config.in
+++ b/src/config.in
@@ -819,6 +819,12 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 /* Define to unlink, rather than empty, mail spool after reading. */
 #undef MAIL_UNLINK_SPOOL
 
+/* Define if the mailer uses flock to interlock the mail spool. */
+#undef MAIL_USE_FLOCK
+
+/* Define if the mailer uses lockf to interlock the mail spool. */
+#undef MAIL_USE_LOCKF
+
 /* Define to support MMDF mailboxes in movemail. */
 #undef MAIL_USE_MMDF
 
-- 
2.39.2