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@(#)wait.1 8.1 (Berkeley) 6/5/93
.Dd June 5, 1993 .Dt WAIT 1 .Os .Sh NAME .Nm wait .Nd await process completion .Sh SYNOPSIS .Nm wait .Op Ar pid .Sh DESCRIPTION If invoked with no arguments, the .Nm wait utility waits until all existing child processes in the background have terminated.
p Available operands: l -tag -width Ds t Ar pid If a .Ar pid operand is specified, and it is the process ID of a background child process that still exists, the .Nm wait utility waits until that process has completed and consumes its status information, without consuming the status information of any other process.
p If a pid operand is specified that is not the process ID of a child background process that still exists, .Nm wait exits without waiting for any processes to complete. .El
p The .Nm wait utility exits with one of the following values: l -tag -width Ds t 0 The .Nm wait utility was invoked with no operands and all of the existing background child processes have terminated, or the process specified by the pid operand exited normally with 0 as its exit status. t >0 The specified process did not exist and its exit status information was not available, or the specified process existed or its exit status information was available, and it terminated with a non-zero exit status. .El
p If the specified process terminated abnormally due to the receipt of a signal, the exit status information of .Nm wait contains that termination status as well. .Sh STANDARDS The .Nm wait command is expected to be .St -p1003.2 compatible.