Thanks for these insights.

Yes, I think that behavior makes sense.
I find the solution to run in a subshell really clean and elegant.

Regards,
Samuel

On Fri, May 28, 2021 at 1:02 PM Stephane Chazelas <stephane@chazelas.org> wrote:

In both cases, tr/yes are being killed (with a SIGPIPE) because
they're trying to write to a pipe that has no reader. [...]

Which is printed (or rather here the "broken pipe" message
corresponding to that death-by-SIGPIPE) because of
PRINT_EXIT_VALUE.

Which is exactly what's supposed to happen when you have that set.

You can run the pipeline in a subshell to suppress this behavior:

( < /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c 32; echo )

PRINT_EXIT_VALUE is disabled in subshells because subshells do not
normally maintain a jobs table like an interactive shell does.

--

Samuel Bancal IT Eng

ENAC-IT GR A0 464

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