NAME

       wait - check child process status

SYNTAX

       #include <wait.h>

       int wait_nohang(&wstat);
       int wait_stop(&wstat);
       int wait_stopnohang(&wstat);
       int wait_pid(&wstat,pid);

       int wait_exitcode(wstat);
       int wait_crashed(wstat);
       int wait_stopped(wstat);
       int wait_stopsig(wstat);

       int pid;
       int wstat;

DESCRIPTION

       wait_nohang looks for zombies (child processes that have exited).  If it sees a zombie, it eliminates the
       zombie, puts the zombie's exit status into wstat, and returns the zombie's  process  ID.   If  there  are
       several zombies, wait_nohang picks one.  If there are children but no zombies, wait_nohang returns 0.  If
       there are no children, wait_nohang returns -1, setting errno appropriately.

       wait_stopnohang is similar to wait_nohang, but it also looks for children that have stopped.

       wait_stop is similar to wait_stopnohang, but if there are children it will pause waiting for one of  them
       to stop or exit.

       wait_pid  waits  for  child process pid to exit.  It eliminates any zombie that shows up in the meantime,
       discarding the exit status.

       wait_stop and wait_pid retry upon error_intr.

STATUS PARSING

       If the child stopped, wait_stopped is nonzero; wait_stopsig is the signal that caused the child to stop.

       If the child exited by crashing, wait_stopped is zero; wait_crashed is nonzero.

       If the child exited normally, wait_stopped is zero;  wait_crashed  is  zero;  and  wait_exitcode  is  the
       child's exit code.

SEE ALSO

       wait(2), error(3)

                                                                                                         wait(3)