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1 files changed, 55 insertions, 0 deletions
diff --git a/sysdeps/unix/bsd/sun/m68k/vfork.S b/sysdeps/unix/bsd/sun/m68k/vfork.S
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+/* Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <sysdep.h>
+
+#ifndef	SYS_vfork
+#define	SYS_vfork	66
+#endif
+
+/* Clone the calling process, but without copying the whole address space.
+   The the calling process is suspended until the the new process exits or is
+   replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
+   and the process ID of the new process to the old process.  */
+.globl ___vfork
+___vfork:
+	/* Pop the return PC value into A0.  */
+	movel sp@+, a0
+
+	/* Push the syscall number and trap into the kernel.  */
+	movel #SYS_vfork, sp@-
+	trap #0
+	bcs error		/* Branch forward if it failed.  */
+
+	/* It succeeded.  See which fork we're in.  D1 is now 0 for the
+	   parent and 1 for the child.  Decrement it to make it -1 (all
+	   bits set) for the parent, and 0 (no bits set) for the child.
+	   Then AND it with D0, so the parent gets D0&-1==R0, and the child
+	   gets D0&0==0.  */
+	decl d1
+	andl d1, d0
+
+	/* Jump to the return PC.  */
+	jmp a0@
+
+error:
+	movel d0, _errno
+	moveq #-1, d0
+	jmp a0@
+
+weak_alias (__vfork, vfork)