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/* Copyright (C) 2008 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by David Bartley <dtbartle@csclub.uwaterloo.ca>.
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>
ENTRY (__vfork)
/* Save the return address */
popq scratch; cfi_adjust_cfa_offset (-8);
/* Call vforkx(0) */
pushq $0
pushq $SYS_SUB_vforkx
pushq scratch
cfi_adjust_cfa_offset (24);
DO_CALL (forksys, 1)
jb 2f
addq $24, %rsp; cfi_adjust_cfa_offset (-24);
/* In the parent process, %rdx == 0, %rax == child pid.
In the child process, %rdx == 1, %rax == parent pid. */
decq %rdx
andq %rdx, %rax
/* Jump to the old return address */
jmp *scratch
2:
/* Restore the return address and jump to the syscall error label */
addq $24, %rsp; cfi_adjust_cfa_offset (-24);
pushq scratch; cfi_adjust_cfa_offset (8);
jmp SYSCALL_ERROR_LABEL
L(pseudo_end):
ret
PSEUDO_END (__vfork)
libc_hidden_def (__vfork)
weak_alias (__vfork, vfork)
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