wait3.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

/*	@(#)wait3.c	4.2	(Berkeley)	12/28/82	*/

/*
 * C library -- wait3
 *
 * pid = wait3(&status, flags, &rusage);
 *
 * pid == -1 if error
 * status indicates fate of process, if given
 * flags may indicate process is not to hang or
 * that untraced stopped children are to be reported.
 * rusage optionally returns detailed resource usage information
 */
#include "SYS.h"


ENTRY(wait3)
	movl	8(ap),r0	/* make it easy for system to get */
	movl	12(ap),r1	/* these extra arguments */
	bispsw	$0xf		/* flags wait3() */
	chmk	$SYS_wait3
	bcc 	noerror
	movl	r0,_errno
	mnegl	$1,r0
	ret
noerror:
	tstl	4(ap)		/* status desired? */
	beql	nostatus	/* no */
	movl	r1,*4(ap)	/* store child's status */
nostatus:
	ret