The function pipe-kill-process
tries to kill the process of a pipe stream.
pipe-stream must be the result of open-pipe. pipe-kill-process
tries to kill the process that open-pipe creates.
The return value nil
means that the process has already died. In this case the process is guaranteed to have died.
The return value t
means that the process was still alive when pipe-kill-process
was called, and it tried to kill it.
On Microsoft Windows, it causes the process to exit, but there may be some delay until it actually exits, so the process may still be alive at the time pipe-kill-process
returns.
On Unix it sends SIGTERM to the process, which normally would cause it to exit, but in principle the process may handle SIGTERM and continue to run.
pipe-kill-process
will kill is the shell or cmd. When open-pipe is called with a list, it executes the process (first element of the list) directly, and pipe-kill-process
kills this process (the different behavior is actually documented in call-system).pipe-kill-process
needs to be be called before the stream is closed by close. On Unix-like systems it works after close too, but for compatibility pipe-kill-process
should not be called after close. nil
, there is a possibility that the child process that open-pipe started died and another process started with the same Process ID, and then pipe-kill-process
may wrongly kill the new process. When open-pipe is called with save-exit-status non-nil, the status of the child process is tracked properly, and pipe-kill-process
is guaranteed to do the right thing. On Windows pipe-kill-process
always does the right thing.LispWorks User Guide and Reference Manual - 20 Sep 2017