connor-brooks / play_stdin.sh Goto Github PK

Thanks for the nice sample code of a simple bash -based 'server' that takes commands from a remote client.

When play_stdin_server.sh exits abnormally (control-C, for example), the /tmp/play_stdin_server pipe is left lying around.

Not a huge deal, but it would be cleaner if the script removed it. If I run the script, do a control-C and run it again, I get an error message as the script tries to create the already existing pipe.

Use the 'trap on EXIT' feature of bash to ensure a cleanup function is run no matter how the script exits - both normally and abnormally

Just before "#Create the pipe", add:

always_run_on_exit () {
   # Use -f so that there is no error if the pipe does not yet exist or was already removed
   rm -f $CONTROLLER_PIP_FILE
}

# No matter how the script exits, ensure pipe gets removed
trap always_run_on_exit EXIT

Then you can remove the 'rm $CONTROLLER_PIPE_FILE' from server_exit() too. Although there's no harm in leaving it there as the 'cleanup_server_fifo' function uses 'rm -f' which won't report an error when trying to remove something that's not there.