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kernc • yesterday at 6:38 PM • 2 replies • view on HN

> language with poor concurrency controls

Few other languages have as many builtins/keywords for concurrency control: &, wait, jobs ...

Replies

Joker_vD • yesterday at 6:52 PM

Yeah, and all those concurrency controls of the shell suck. Here's a snippet to run N commands in parallel, wait for all of them, while supporting interrupting them with simple Ctrl+C:

    (
        trap 'kill 0' SIGINT;
        for i in {1..$N}
        do
            whatever_command $i &
        done
        wait
    )
The parentheses are absolutely crucial there for some reason, the { } won't give you pass-through of SIGINT. No wonder people keep re-inventing PID files, manually tracking $! and all kinds of other crazy bullshit that work 90% of the time, but sometimes fail to properly terminate the runaway children.
➕ show 1 reply
nagaiaida • yesterday at 7:34 PM

perhaps that's more an indictment of most programming languages