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From: Greg Wooledge <wooledg@eeg.ccf.org>
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Subject: Re: Protect Loop Execution with Traps
Date: Wed, 29 Jan 2020 09:33:52 -0500
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On Wed, Jan 29, 2020 at 01:05:32PM +0700, Robert Elz wrote:
> and (with all respect to Gred) please avoid archaic uses, and use the
> commands as they're currently specified, while "trap - INT" and "trap INT"
> do the same thing, the former is the standard way, similarly for
> "kill -INT ..." and "kill -s INT ..." the latter is the modern version.

I had <https://www.cons.org/cracauer/sigint.html> open at the time,
and got the syntax from there.  He actually uses the numeric signal
specifiers ("trap 2"), which I replaced with the modern standard naming
strings; but I didn't replace the legacy single-argument form with
the "-" form.  Bash, of course, accepts both.

You're not going to talk me into using "kill -s" any time soon, though.
I don't think I've *ever* seen anyone use that.

>   | I'm thinking, put "trap INT; kill -INT $$" inside of it's own function,

Yeah, that's pretty common.

sigint_handler() {
    trap - INT
    kill -INT $$
}
trap sigint_handler INT