From 2337d83d410d6a64ad7707fe7f093fc654f66e4f Mon Sep 17 00:00:00 2001
From: David Levine <levinedl@acm.org>
Date: Sun, 6 May 2012 21:53:18 -0500
Subject: [PATCH] Default to fcntl locking for AIX, Cygwin, and Linux. 
 Without it on Cygwin, nmh is unusable on FAT32 filesystems.

Default to flock on FreeBSD.
---
 MACHINES     |    3 +++
 configure.ac |   10 ++++++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/MACHINES b/MACHINES
index ba36863..482941a 100644
--- a/MACHINES
+++ b/MACHINES
@@ -27,6 +27,9 @@ Be sure to install these Cygwin packages:
   libncurses10
   libncurses-devel
 
+Note that the -link switch to refile cannot be used on FAT32 and
+similar filesystems.
+
 --------------------------------------
 HPUX:
 
diff --git a/configure.ac b/configure.ac
index 70490ca..ece8090 100644
--- a/configure.ac
+++ b/configure.ac
@@ -71,6 +71,12 @@ AC_DEFINE_UNQUOTED([BACKUP_PREFIX], "$backup_prefix",
     [The prefix that is prepended to the name of message files when they are "removed" by rmm. This should typically be `,' or `#'.])dnl
 
 dnl What method of locking to use?
+AS_CASE(["$host_os"],
+  [aix*|cygwin*|linux*],
+    [default_locktype="fcntl"; default_locking=FCNTL_LOCKING],
+  [freebsd*], [default_locktype="flock"; default_locking=FLOCK_LOCKING],
+  [default_locktype="dot"; default_locking=DOT_LOCKING])
+
 AC_ARG_WITH(locking,
   AS_HELP_STRING([--with-locking=@<:@dot|fcntl|flock|lockf@:>@],
   [specify the file locking method]))
@@ -88,8 +94,8 @@ elif test x"$with_locking" = x"fcntl"; then
   LOCKTYPE="fcntl"
   AC_DEFINE(FCNTL_LOCKING, 1, [Define to use fnctl() based locking.])dnl
 else
-  LOCKTYPE="dot"
-  AC_DEFINE(DOT_LOCKING)dnl
+  LOCKTYPE="$default_locktype"
+  AC_DEFINE_UNQUOTED($default_locking, 1)dnl
 fi
 
 dnl Should we use a locking directory?
-- 
1.7.10.4