Index: Build.sh
===================================================================
RCS file: /cvs/src/bin/mksh/Build.sh,v
retrieving revision 1.508
diff -u -r1.508 Build.sh
--- Build.sh    4 Jan 2012 08:56:51 -0000   1.508
+++ Build.sh    6 Jan 2012 01:19:57 -0000
@@ -1327,6 +1327,8 @@
 # Environment: library functions
 #
 ac_testn flock_ex '' 'flock and mmap' <<-'EOF'
+   #define MKSH_INCLUDES_ONLY
+   #include "sh.h"
    #include <sys/types.h>
    #if HAVE_SYS_FILE_H
    #include <sys/file.h>
Index: histrap.c
===================================================================
RCS file: /cvs/src/bin/mksh/histrap.c,v
retrieving revision 1.117
diff -u -r1.117 histrap.c
--- histrap.c   31 Dec 2011 00:48:09 -0000  1.117
+++ histrap.c   6 Jan 2012 01:52:44 -0000
@@ -26,6 +26,20 @@
 #include <sys/file.h>
 #endif

+#if defined(__sun) || defined(__MSYS__)
+int emul_flock(int fd, int cmd)
+{    struct flock f;
+    memset(&f, 0, sizeof (f));
+    if (cmd & LOCK_UN)
+        f.l_type = F_UNLCK;
+    if (cmd & LOCK_SH)
+        f.l_type = F_RDLCK;
+    if (cmd & LOCK_EX)
+        f.l_type = F_WRLCK;
+    return fcntl(fd, (cmd & LOCK_NB) ? F_SETLK : F_SETLKW, &f);
+}
+#endif
+
 __RCSID("$MirOS: src/bin/mksh/histrap.c,v 1.117 2011/12/31 00:47:45 tg Exp $");

 Trap sigtraps[NSIG + 1];
Index: sh.h
===================================================================
RCS file: /cvs/src/bin/mksh/sh.h,v
retrieving revision 1.519
diff -u -r1.519 sh.h
--- sh.h    4 Jan 2012 19:10:00 -0000   1.519
+++ sh.h    6 Jan 2012 01:52:33 -0000
@@ -151,6 +151,33 @@
 #define __SCCSID(x)        __IDSTRING(sccsid,x)
 #endif

+#ifndef LOCK_SH
+#define   LOCK_SH   1    /* shared lock */
+#define   LOCK_EX   2    /* exclusive lock */
+#define   LOCK_NB   4    /* don't block when locking */
+#define   LOCK_UN   8    /* unlock */
+#endif
+#if defined(__sun) || defined(__MSYS__)
+#include <sys/fcntl.h>
+int emul_flock(int fd, int cmd);
+
+#ifdef MKSH_INCLUDES_ONLY
+int emul_flock(int fd, int cmd)
+{    struct flock f;
+    memset(&f, 0, sizeof (f));
+    if (cmd & LOCK_UN)
+        f.l_type = F_UNLCK;
+    if (cmd & LOCK_SH)
+        f.l_type = F_RDLCK;
+    if (cmd & LOCK_EX)
+        f.l_type = F_WRLCK;
+    return fcntl(fd, (cmd & LOCK_NB) ? F_SETLK : F_SETLKW, &f);
+}
+#endif
+
+#define flock(f,c)      emul_flock(f,c)
+#endif
+
 #ifdef EXTERN
 __RCSID("$MirOS: src/bin/mksh/sh.h,v 1.519 2012/01/04 19:09:36 tg Exp $");
 #endif