xref: /original-bsd/sys/sys/wait.h (revision 57124d5e)
1 /*
2  * Copyright (c) 1982, 1986 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)wait.h	7.2 (Berkeley) 10/13/86
7  */
8 
9 /*
10  * This file holds definitions relevent to the wait system call.
11  * Some of the options here are available only through the ``wait3''
12  * entry point; the old entry point with one argument has more fixed
13  * semantics, never returning status of unstopped children, hanging until
14  * a process terminates if any are outstanding, and never returns
15  * detailed information about process resource utilization (<vtimes.h>).
16  */
17 
18 #ifndef ENDIAN
19 #include <machine/machparam.h>
20 #endif
21 
22 /*
23  * Structure of the information in the first word returned by both
24  * wait and wait3.  If w_stopval==WSTOPPED, then the second structure
25  * describes the information returned, else the first.  See WUNTRACED below.
26  */
27 union wait	{
28 	int	w_status;		/* used in syscall */
29 	/*
30 	 * Terminated process status.
31 	 */
32 	struct {
33 #if ENDIAN == LITTLE
34 		unsigned short	w_Termsig:7;	/* termination signal */
35 		unsigned short	w_Coredump:1;	/* core dump indicator */
36 		unsigned short	w_Retcode:8;	/* exit code if w_termsig==0 */
37 #endif
38 #if ENDIAN == BIG
39 		unsigned short	w_Filler;	/* upper bits filler */
40 		unsigned char	w_Retcode;	/* exit code if w_termsig==0 */
41 		unsigned char	w_Coredump:1;	/* core dump indicator */
42 		unsigned char	w_Termsig:7;	/* termination signal */
43 #endif
44 	} w_T;
45 	/*
46 	 * Stopped process status.  Returned
47 	 * only for traced children unless requested
48 	 * with the WUNTRACED option bit.
49 	 */
50 	struct {
51 #if ENDIAN == LITTLE
52 		unsigned short	w_Stopval:8;	/* == W_STOPPED if stopped */
53 		unsigned short	w_Stopsig:8;	/* signal that stopped us */
54 #else
55 		unsigned short	w_Filler;	/* upper bits filler */
56 		unsigned char	w_Stopsig;	/* signal that stopped us */
57 		unsigned char	w_Stopval;	/* == W_STOPPED if stopped */
58 #endif
59 	} w_S;
60 };
61 #define	w_termsig	w_T.w_Termsig
62 #define w_coredump	w_T.w_Coredump
63 #define w_retcode	w_T.w_Retcode
64 #define w_stopval	w_S.w_Stopval
65 #define w_stopsig	w_S.w_Stopsig
66 
67 
68 #define	WSTOPPED	0177	/* value of s.stopval if process is stopped */
69 
70 /*
71  * Option bits for the second argument of wait3.  WNOHANG causes the
72  * wait to not hang if there are no stopped or terminated processes, rather
73  * returning an error indication in this case (pid==0).  WUNTRACED
74  * indicates that the caller should receive status about untraced children
75  * which stop due to signals.  If children are stopped and a wait without
76  * this option is done, it is as though they were still running... nothing
77  * about them is returned.
78  */
79 #define WNOHANG		1	/* dont hang in wait */
80 #define WUNTRACED	2	/* tell about stopped, untraced children */
81 
82 #define WIFSTOPPED(x)	((x).w_stopval == WSTOPPED)
83 #define WIFSIGNALED(x)	((x).w_stopval != WSTOPPED && (x).w_termsig != 0)
84 #define WIFEXITED(x)	((x).w_stopval != WSTOPPED && (x).w_termsig == 0)
85