--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/usr/src/lib/libc/port/gen/sh_locks.c	Tue Jun 14 00:00:00 2005 -0700
@@ -0,0 +1,83 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License").  You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include "synonyms.h"
+#include <mtlib.h>
+#include <sys/types.h>
+#include <synch.h>
+#include <thread.h>
+#include "libc.h"
+
+/*
+ * fork1-safety.
+ * These three routines were used to make some libc interfaces fork1-safe.
+ * With the merge of libthread into libc, almost all libc internal-only
+ * locks are acquired via lmutex_lock() or lrw_rdlock()/lrw_wrlock(),
+ * which makes them automatically fork1-safe (as well as async-signal
+ * safe), so these functions are now used only for the locks that cannot
+ * be used with lmutex_lock or lrw_rdlock()/lrw_wrlock().
+ */
+
+extern void atexit_locks(void);
+extern void atexit_unlocks(void);
+
+extern void stdio_locks(void);
+extern void stdio_unlocks(void);
+
+static void
+libc_prepare_atfork(void)
+{
+	atexit_locks();
+	stdio_locks();
+}
+
+static void
+libc_child_atfork(void)
+{
+	stdio_unlocks();
+	atexit_unlocks();
+}
+
+static void
+libc_parent_atfork(void)
+{
+	stdio_unlocks();
+	atexit_unlocks();
+}
+
+/* called from libc_init() */
+void
+atfork_init(void)
+{
+	/* same as pthread_atfork() but private to libc */
+	extern int _private_pthread_atfork(void (*)(void),
+		void (*)(void), void (*)(void));
+
+	(void) _private_pthread_atfork(libc_prepare_atfork,
+		libc_parent_atfork, libc_child_atfork);
+}