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/* Copyright (C) 2001, 2002, 2004 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 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 <features.h>
#include <sys/syscall.h>
/* 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. */
#ifndef __NR_vfork
/* No vfork so use fork instead */
strong_alias(fork,vfork)
strong_alias(vfork,__libc_fork)
#else
.text
.global vfork
.type vfork,%function
.align 16
vfork:
/* Pop the return PC value into RDI. We need a register that
is preserved by the syscall and that we're allowed to destroy. */
popq %rdi
/* Stuff the syscall number in RAX and enter into the kernel. */
movl $__NR_vfork, %eax
syscall
/* Push back the return PC. */
pushq %rdi
cmpl $-4095, %eax
jae __syscall_error /* Branch forward if it failed. */
/* Normal return. */
ret
.size vfork,.-vfork
#endif /* __NR_vfork */
libc_hidden_def(vfork)
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