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/* Copyright (C) 1999, 2002, 2003, 2010 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Schwab <schwab@gnu.org>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#include <kernel-features.h>
#ifndef SAVE_PID
#define SAVE_PID
#endif
#ifndef RESTORE_PID
#define RESTORE_PID
#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. */
ENTRY (__vfork)
#ifdef __NR_vfork
/* SAVE_PID clobbers call-clobbered registers and
saves data in D1 and A1. */
SAVE_PID
/* Pop the return PC value into A0. */
movel %sp@+, %a0
/* Stuff the syscall number in D0 and trap into the kernel. */
movel #SYS_ify (vfork), %d0
trap #0
RESTORE_PID
tstl %d0
jmi .Lerror /* Branch forward if it failed. */
/* Jump to the return PC. */
jmp %a0@
.Lerror:
/* Push back the return PC. */
movel %a0,%sp@-
# ifdef __ASSUME_VFORK_SYSCALL
# ifndef PIC
jbra SYSCALL_ERROR_LABEL
# endif
# else
/* Check if vfork syscall is known at all. */
movel #-ENOSYS,%d1
cmpl %d0,%d1
jne SYSCALL_ERROR_LABEL
# endif
#endif
#ifndef __ASSUME_VFORK_SYSCALL
/* If we don't have vfork, fork is close enough. */
movel #SYS_ify (fork), %d0
trap #0
tstl %d0
jmi SYSCALL_ERROR_LABEL
rts
#endif
PSEUDO_END (__vfork)
libc_hidden_def (__vfork)
weak_alias (__vfork, vfork)
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