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- /* Copyright (C) 1991 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
- ___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. */
- tstl d1 /* If D1 is zero, we're the parent. */
- beq parent
-
- /* We're the child. Clear D0. */
- clrl d0
-
- /* Jump to the return PC. */
- parent: jmp a0@
-
- error:
- movel d0, _errno
- moveq #-1, d0
- jmp a0@
-