running as normal unprivileged user on linux. steps to reproduce:

1. issue an invalid command e.g. qme --help
2. observe that error message received and then application begins idling
3. introduce signal interrupt key sequence ctrl+c
4. application acknowledges interrupt signal received and states shutdown is beginning
5. application hangs indefinitely and doesn't shut down

2022/01/26 21:42:13 failed to execute command --help: exec: "--help": executable file not found in $PATH
2022/01/26 21:42:13 idling...
^C2022/01/26 22:04:11 interrupt signal received
2022/01/26 22:04:11 shutting down

As it is, qme listens on /tmp/qme.sock. This will fail in a multi-user environment where more that one user is attempting to queue jobs. Instead use a socket name based on e.g. the user's numerical id — i.e., /tmp/qme-1234.sock for the user with the numerical id 1234.

Ideally, the socket should be created in the directory pointed to by the $TMPDIR variable, but a socket-per-user will do for a start.

:link: https://en.wikipedia.org/wiki/TMPDIR

It would be helpful if the qme command accepted at least a -h option for a minimal help text — e.g.:

$ qme -h
usage: qme [-h] COMMAND [ARG ...]

positional arguments:
  COMMAND     command to run
  ARG         optional argument(s)

options:
  -h, --help  show this help message and exit

As it is, qme will try ro queue -h as a command:

$ qme -h
2022/06/20 15:22:22 assuming server role
2022/06/20 15:22:22 enqueueing '-h'
2022/06/20 15:22:22 failed to execute command -h: exec: "-h": executable file not found in $PATH
2022/06/20 15:22:22 idling...
2022/06/20 15:22:22 listening on /tmp/qme.sock

PS: A -V/--version option would also come in handy — e.g., for bug reports.