Current File : //usr/local/share/zsh/5.8/help/wait
wait [ job ... ]
Wait for the specified jobs or processes. If job is not given
then all currently active child processes are waited for. Each
job can be either a job specification or the process ID of a job
in the job table. The exit status from this command is that of
the job waited for. If job represents an unknown job or process
ID, a warning is printed (unless the POSIX_BUILTINS option is set)
and the exit status is 127.
It is possible to wait for recent processes (specified by process
ID, not by job) that were running in the background even if the
process has exited. Typically the process ID will be recorded by
capturing the value of the variable $! immediately after the
process has been started. There is a limit on the number of
process IDs remembered by the shell; this is given by the value of
the system configuration parameter CHILD_MAX. When this limit is
reached, older process IDs are discarded, least recently started
processes first.
Note there is no protection against the process ID wrapping, i.e.
if the wait is not executed soon enough there is a chance the
process waited for is the wrong one. A conflict implies both
process IDs have been generated by the shell, as other processes
are not recorded, and that the user is potentially interested in
both, so this problem is intrinsic to process IDs.
Mini Shell