parallel does not complete and exit its own process

[omac777]

Scenario: We launch two different tasks in parallel. Let's say two bash scripts. One sleeps and echos that is done. The other sleeps and doesn't echo and simply exits.

If the entire bash script does not send any output to console or error and exits, it may not be perceived as completed.

My hunch

The wrong exit code or wrong signal is sent and parallel doesn't capture that signal and never perceives that bash script as completed. As a result all of the parallel did not complete and did not exit its own process.

OR

The empty output or empty error never gets closed because it never got used. The buffer that was reading the output console or error console output never closed or exited so it never perceived that thread to be completed either and hung on reading an empty file expecting to read something. As a result all of the parallel did not complete and did not exit its own process.

[mmstick]

For now, it's best to stick with GNU Parallel, as this is no longer maintained. One day this will get rewritten with tokio and futures and replaced.