wait.h

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/*	$NetBSD: wait.h,v 1.11 1996/04/09 20:55:51 cgd Exp $	*/

/*
 * Copyright (c) 1982, 1986, 1989, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)wait.h	8.2 (Berkeley) 7/10/94
 */

#ifndef _SYS_WAIT_H_
#define _SYS_WAIT_H_

/*
 * This file holds definitions relevent to the wait4 system call
 * and the alternate interfaces that use it (wait, wait3, waitpid).
 */

/*
 * Macros to test the exit status returned by wait
 * and extract the relevant values.
 */
#ifdef _POSIX_SOURCE
#define	_W_INT(i)	(i)
#else
#define	_W_INT(w)	(*(int *)&(w))	/* convert union wait to int */
#define	WCOREFLAG	0200
#endif

#define	_WSTATUS(x)	(_W_INT(x) & 0177)
#define	_WSTOPPED	0177		/* _WSTATUS if process is stopped */
#define WIFSTOPPED(x)	(_WSTATUS(x) == _WSTOPPED)
#define WSTOPSIG(x)	(_W_INT(x) >> 8)
#define WIFSIGNALED(x)	(_WSTATUS(x) != _WSTOPPED && _WSTATUS(x) != 0)
#define WTERMSIG(x)	(_WSTATUS(x))
#define WIFEXITED(x)	(_WSTATUS(x) == 0)
#define WEXITSTATUS(x)	(_W_INT(x) >> 8)
#ifndef _POSIX_SOURCE
#define WCOREDUMP(x)	(_W_INT(x) & WCOREFLAG)

#define	W_EXITCODE(ret, sig)	((ret) << 8 | (sig))
#define	W_STOPCODE(sig)		((sig) << 8 | _WSTOPPED)
#endif

/*
 * Option bits for the third argument of wait4.  WNOHANG causes the
 * wait to not hang if there are no stopped or terminated processes, rather
 * returning an error indication in this case (pid==0).  WUNTRACED
 * indicates that the caller should receive status about untraced children
 * which stop due to signals.  If children are stopped and a wait without
 * this option is done, it is as though they were still running... nothing
 * about them is returned.
 */
#define WNOHANG		1	/* don't hang in wait */
#define WUNTRACED	2	/* tell about stopped, untraced children */

#ifndef _POSIX_SOURCE
/* POSIX extensions and 4.2/4.3 compatability: */

/*
 * Tokens for special values of the "pid" parameter to wait4.
 */
#define	WAIT_ANY	(-1)	/* any process */
#define	WAIT_MYPGRP	0	/* any process in my process group */

#include <machine/endian.h>

/*
 * Deprecated:
 * Structure of the information in the status word returned by wait4.
 * If w_stopval==WSTOPPED, then the second structure describes
 * the information returned, else the first.
 */
union wait {
	int	w_status;		/* used in syscall */
	/*
	 * Terminated process status.
	 */
	struct {
#if BYTE_ORDER == LITTLE_ENDIAN
		unsigned int	w_Termsig:7,	/* termination signal */
				w_Coredump:1,	/* core dump indicator */
				w_Retcode:8,	/* exit code if w_termsig==0 */
				w_Filler:16;	/* upper bits filler */
#endif
#if BYTE_ORDER == BIG_ENDIAN
		unsigned int	w_Filler:16,	/* upper bits filler */
				w_Retcode:8,	/* exit code if w_termsig==0 */
				w_Coredump:1,	/* core dump indicator */
				w_Termsig:7;	/* termination signal */
#endif
	} w_T;
	/*
	 * Stopped process status.  Returned
	 * only for traced children unless requested
	 * with the WUNTRACED option bit.
	 */
	struct {
#if BYTE_ORDER == LITTLE_ENDIAN
		unsigned int	w_Stopval:8,	/* == W_STOPPED if stopped */
				w_Stopsig:8,	/* signal that stopped us */
				w_Filler:16;	/* upper bits filler */
#endif
#if BYTE_ORDER == BIG_ENDIAN
		unsigned int	w_Filler:16,	/* upper bits filler */
				w_Stopsig:8,	/* signal that stopped us */
				w_Stopval:8;	/* == W_STOPPED if stopped */
#endif
	} w_S;
};
#define	w_termsig	w_T.w_Termsig
#define w_coredump	w_T.w_Coredump
#define w_retcode	w_T.w_Retcode
#define w_stopval	w_S.w_Stopval
#define w_stopsig	w_S.w_Stopsig

#define	WSTOPPED	_WSTOPPED
#endif /* _POSIX_SOURCE */

#ifndef _KERNEL
#include <sys/types.h>
#include <sys/cdefs.h>

__BEGIN_DECLS
struct rusage;	/* forward declaration */

pid_t	wait __P_((int *));
pid_t	waitpid __P_((pid_t, int *, int));
#ifndef _POSIX_SOURCE
pid_t	wait3 __P_((int *, int, void *));
pid_t	wait4 __P_((pid_t, int *, int, void *));
#endif
__END_DECLS
#endif

#endif /* !_SYS_WAIT_H_ */