1 /* $NetBSD: fork.S,v 1.10 2006/01/06 05:11:29 uwe Exp $ */
4 * Copyright (c) 1990 The Regents of the University of California.
7 * This code is derived from software contributed to Berkeley by
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34 * from: @(#)fork.s 5.1 (Berkeley) 4/23/90
37 #include <machine/asm.h>
38 #if defined(SYSLIBC_SCCS) && !defined(lint)
39 RCSID("$NetBSD: fork.S,v 1.10 2006/01/06 05:11:29 uwe Exp $")
40 #endif /* SYSLIBC_SCCS and not lint */
47 * r1 == 0 in parent process, r1 == 1 in child process.
48 * r0 == pid of child in parent, r0 == pid of parent in child.
56 add #0xff, r1 /* from 1 to 0 in child, 0 to -1 in parent */
58 and r1, r0 /* 0 in child, child pid in parent */
63 SET_ENTRY_SIZE(__fork)