include/sys/wait.h

   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:
   5  *
   6  *                               High byte   Low byte
   7  *                              +---------------------+
   8  *      exit(status)            |  status  |    0     |
   9  *                              +---------------------+
  10  *      killed by signal        |    0     |  signal  |
  11  *                              +---------------------+
  12  *      stopped (job control)   |  signal  |   0177   |
  13  *                              +---------------------+
  14  */
  15
  16 #ifndef _WAIT_H
  17 #define _WAIT_H
  18
  19 #ifndef _TYPES_H
  20 #include <minix/types.h>
  21 #endif
  22
  23 #define _LOW(v)         ( (v) & 0377)
  24 #define _HIGH(v)        ( ((v) >> 8) & 0377)
  25
  26 #define WNOHANG         1       /* do not wait for child to exit */
  27 #define WUNTRACED       2       /* for job control; not implemented */
  28
  29 #define WIFEXITED(s)    (_LOW(s) == 0)                      /* normal exit */
  30 #define WEXITSTATUS(s)  (_HIGH(s))                          /* exit status */
  31 #define WTERMSIG(s)     (_LOW(s) & 0177)                    /* sig value */
  32 #define WIFSIGNALED(s)  ((((unsigned int)(s)-1) & 0xFFFFU) < 0xFFU) /* signaled */
  33 #define WIFSTOPPED(s)   (_LOW(s) == 0177)                   /* stopped */
  34 #define WSTOPSIG(s)     (_HIGH(s) & 0377)                   /* stop signal */
  35
  36 /* Function Prototypes. */
  37 _PROTOTYPE( pid_t wait, (int *_stat_loc)                                   );
  38 _PROTOTYPE( pid_t waitpid, (pid_t _pid, int *_stat_loc, int _options)      );
  39
  40 #endif /* _WAIT_H */