From ef5f752a4ae818d9c739a064410a02fa48a477e3 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <tridge@samba.org>
Date: Tue, 15 Dec 1998 03:16:24 +0000
Subject: [PATCH 1/1] on Linux force fcntl/mmap based shared memory and on
 other systems force IPC/shmem based shared memory.

---
 source/include/includes.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/source/include/includes.h b/source/include/includes.h
index 58c6ee01bdc..824a5bde5db 100644
--- a/source/include/includes.h
+++ b/source/include/includes.h
@@ -46,6 +46,19 @@
 #endif
 
 
+/* if we have both SYSV IPC and shared mmap then we need to choose. For most
+   systems it is much faster to use SYSV IPC, but under Linux it is
+   about 5 times faster to use fcntl, so for Linux systems we force
+   fcntl based locking */
+#if (defined(HAVE_SYSV_IPC) && defined(HAVE_SHARED_MMAP))
+# ifdef LINUX
+#  undef HAVE_SYSV_IPC
+# else
+#  undef HAVE_SHARED_MMAP
+# endif
+#endif
+
+
 #include <sys/types.h>
 
 #ifdef TIME_WITH_SYS_TIME
-- 
2.34.1