glibc/sysdeps/unix/bsd/vax/vfork.S
1995-03-06 00:22:30 +00:00

58 lines
1.6 KiB
ArmAsm

/* Copyright (C) 1991, 1992, 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
error: jmp syscall_error
___vfork:
.word 0
/* Save our return address in R2, and return to code below. */
movl 16(fp), r2
movab unwind, 16(fp)
ret
unwind:
/* Do the system call. */
chmk $SYS_vfork
bcs error
tstl r1
beq parent
/* We are the child. Return zero. */
clrl r0
/* Return to the saved address. */
parent: jmp (r2)
.globl _errno
error:
movl r0, _errno
mnegl $1, r0
jmp (r2)
weak_alias (__vfork, vfork)