05fdf2dfc9
* sysdeps/unix/bsd/vax/vfork.S: Missed double occurences of "the the" in one line - fixed it. * sysdeps/unix/bsd/sun/m68k/vfork.S: Likewise. * sysdeps/unix/bsd/hp/m68k/vfork.S: Likewise. * posix/unistd.h: Likewise 1998-05-20 Andreas Jaeger <aj@arthur.rhein-neckar.de>
56 lines
1.9 KiB
ArmAsm
56 lines
1.9 KiB
ArmAsm
/* Copyright (C) 1991, 1994, 1995, 1997 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., 59 Temple Place - Suite 330,
|
|
Boston, MA 02111-1307, USA. */
|
|
|
|
#include <sysdep.h>
|
|
|
|
#ifndef SYS_vfork
|
|
#define SYS_vfork 66
|
|
#endif
|
|
|
|
/* Clone the calling process, but without copying the whole address space.
|
|
The calling process is suspended until 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. */
|
|
moveal sp@+, a0
|
|
|
|
/* Stuff the syscall number in D0 and trap into the kernel. */
|
|
movel #SYS_vfork, d0
|
|
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. */
|
|
subl #1, d1
|
|
andl d1, d0
|
|
|
|
/* Jump to the return PC. */
|
|
jmp a0@
|
|
|
|
error:
|
|
movel d0, _errno
|
|
moveq #-1, d0
|
|
jmp a0@
|
|
|
|
weak_alias (__vfork, vfork)
|