[unix-history] / usr / src / sys / sys / wait.h

/*
* Copyright (c) 1982, 1986, 1989 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
*      @(#)wait.h      7.8 (Berkeley) %G%
*/

/*
* 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 second 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       /* dont 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 */

#ifndef BYTE_ORDER
#include <machine/endian.h>
#endif

/*
* 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 short  w_Termsig:7;    /* termination signal */
               unsigned short  w_Coredump:1;   /* core dump indicator */
               unsigned short  w_Retcode:8;    /* exit code if w_termsig==0 */
#endif
#if BYTE_ORDER == BIG_ENDIAN 
               unsigned short  w_Filler;       /* upper bits filler */
               unsigned char   w_Retcode;      /* exit code if w_termsig==0 */
               unsigned char   w_Coredump:1;   /* core dump indicator */
               unsigned char   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 short  w_Stopval:8;    /* == W_STOPPED if stopped */
               unsigned short  w_Stopsig:8;    /* signal that stopped us */
#else
               unsigned short  w_Filler;       /* upper bits filler */
               unsigned char   w_Stopsig;      /* signal that stopped us */
               unsigned char   w_Stopval;      /* == 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 */