1 /* The <sys/wait.h> header contains macros related to wait(). The value
2 * returned by wait() and waitpid() depends on whether the process
3 * terminated by an exit() call, was killed by a signal, or was stopped
4 * due to job control, as follows:
7 * +---------------------+
8 * exit(status) | status | 0 |
9 * +---------------------+
10 * killed by signal | 0 | signal |
11 * +---------------------+
12 * stopped (job control) | signal | 0177 |
13 * +---------------------+
19 #define _LOW(v) ( (v) & 0377)
20 #define _HIGH(v) ( ((v) >> 8) & 0377)
22 #define WNOHANG 1 /* do not wait for child to exit */
23 #define WUNTRACED 2 /* for job control; not implemented */
25 #define WIFEXITED(s) (_LOW(s) == 0) /* normal exit */
26 #define WEXITSTATUS(s) (_HIGH(s)) /* exit status */
27 #define WTERMSIG(s) (_LOW(s) & 0177) /* sig value */
28 #define WIFSIGNALED(s) (((unsigned int)(s)-1 & 0xFFFF) < 0xFF) /* signaled */
29 #define WIFSTOPPED(s) (_LOW(s) == 0177) /* stopped */
30 #define WSTOPSIG(s) (_HIGH(s) & 0377) /* stop signal */
32 /* Function Prototypes. */
37 _PROTOTYPE( pid_t wait, (int *_stat_loc) );
38 _PROTOTYPE( pid_t waitpid, (pid_t _pid, int *_stat_loc, int _options) );