wait

Function

wait invokes the wait callable service to obtain the status of any child process that has ended or stopped. You can use the wait service to obtain the status of a process that is being debugged with the ptrace facilities. The term child refers to a child process created by a fork as well as a process attached by ptrace.

Parameters

stem

The name of a stem variable used to return the information. Upon return, stem.0 contains the number of variables returned. To access the information in the stem variables, you can specify a numeric value (see REXX predefined variables) or the predefined variables beginning with W_ that derive the appropriate numeric value.

Variable	Description
W_CONTINUED	Process continued from stop.
W_EXITSTATUS	The exit status of the child process.
W_IFEXITED	The child process ended normally.
W_IFSIGNALED	The child process ended because of a signal that was not caught.
W_IFSTOPPED	Wait if the child process is stopped.
W_STAT3	Byte 3 of the BPXYWAST macro. See BPXYWAST — Map the wait status word in z/OS UNIX System Services Programming: Assembler Callable Services Reference .
W_STAT4	Byte 4 of the BPXYWAST macro. See BPXYWAST — Map the wait status word in z/OS UNIX System Services Programming: Assembler Callable Services Reference.
W_STOPSIG	The signal number that caused the child process to stop.
W_TERMSIG	The signal number that caused the child process to end.

Usage notes

1. The wait service suspends execution of the calling thread until one of the requested child or debugged processes ends or until it obtains information about the process that ended. If a child or debugged process has already ended but its status has not been reported when wait is called, the routine immediately returns with that status information to the caller.
2. If the WUNTRACED option is specified, the foregoing also applies for stopped children or stopped debugged processes.
3. The wait service always returns status for stopped debugged processes, even if WUNTRACED is not specified.
4. If status is available for one or more processes, the order in which the status is reported is unspecified.