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     WAIT(2)                                                   WAIT(2)

          wait - wait for a process to exit

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

          int wait(Waitmsg *w)

          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:

               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.


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

          Sets errstr.