procexec/print_wait_status.c

/* print_wait_status.c

   Dissect and print the process termination status returned by wait()
   and related calls.
*/
#define _GNU_SOURCE     /* Get strsignal() declaration from <string.h> */
#include <string.h>
#include <sys/wait.h>
#include "print_wait_status.h"  /* Declaration of printWaitStatus() */
#include "tlpi_hdr.h"

/* NOTE: The following function employs printf(), which is not
   async-signal-safe (see Section 21.1.2). As such, this function is
   also not async-signal-safe (i.e., beware of calling it from a
   SIGCHLD handler). */

void                    /* Examine a wait() status using the W* macros */
printWaitStatus(const char *msg, int status)
{
    if (msg != NULL)
        printf("%s", msg);

    if (WIFEXITED(status)) {
        printf("child exited, status=%d\n", WEXITSTATUS(status));

    } else if (WIFSIGNALED(status)) {
        printf("child killed by signal %d (%s)",
                WTERMSIG(status), strsignal(WTERMSIG(status)));
#ifdef WCOREDUMP        /* Not in SUSv3, may be absent on some systems */
        if (WCOREDUMP(status))
            printf(" (core dumped)");
#endif
        printf("\n");

    } else if (WIFSTOPPED(status)) {
        printf("child stopped by signal %d (%s)\n",
                WSTOPSIG(status), strsignal(WSTOPSIG(status)));

#ifdef WIFCONTINUED     /* SUSv3 has this, but older Linux versions and
                           some other UNIX implementations don't */
    } else if (WIFCONTINUED(status)) {
        printf("child continued\n");
#endif

    } else {            /* Should never happen */
        printf("what happened to this child? (status=%x)\n",
                (unsigned int) status);
    }
}