man.postnix Miscellaneous man pages of Plan 9 related material

     WAIT(2)                                                   WAIT(2)

     NAME
          wait - wait for a process to exit

     SYNOPSIS
          #include <u.h>
          #include <libc.h>

          int wait(Waitmsg *w)

     DESCRIPTION
          Wait causes a process to wait for any child process (see
          fork(2)) to exit.  It returns the pid of a child that has
          exited and fills in w with more information about the child.
          W points to a Waitmsg, which has this structure:

               typedef
               struct Waitmsg
               {
                     char pid[12];         /* of loved one */
                     char time[3*12];      /* of loved one & descendants */
                     char msg[ERRLEN];
               } Waitmsg;

          Pid is the child's process id.  The time array contains the
          time the child and its descendants spent in user code, the
          time spent in system calls, and the child's elapsed real
          time, all in units of milliseconds.  All integers in a
          Waitmsg are formatted as right-justified textual numbers in
          11-byte fields followed by a blank. Msg contains the message
          that the child specified in exits(2). For a normal exit,
          msg[0] is zero, otherwise msg is prefixed by the process
          name, a blank, the process id, and a colon.

          If there are no more children to wait for, wait returns
          immediately, with return value -1.

     SOURCE
          /sys/src/libc/9syscall

     SEE ALSO
          fork(2), exits(2), the wait file in proc(3)

     DIAGNOSTICS
          Sets errstr.

     Page 1                       Plan 9            (printed 11/18/24)