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Groups > gnu.bash.bug > #16723

Re: process substitution error handling

Path csiph.com!goblin2!goblin1!goblin.stu.neva.ru!usenet.stanford.edu!not-for-mail
From Eli Schwartz <eschwartz@archlinux.org>
Newsgroups gnu.bash.bug
Subject Re: process substitution error handling
Date Thu, 6 Aug 2020 13:09:23 -0400
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On 8/6/20 12:36 PM, kfm@plushkava.net wrote:
> On 06/08/2020 17:21, Eli Schwartz wrote:
>> On 8/6/20 11:31 AM, Jason A. Donenfeld wrote:
>>> That doesn't always work:
>>>
>>> set -e
>>> while read -r line; do
>>>         echo "$line" &
>>> done < <(echo 1; sleep 1; echo 2; sleep 1; exit 77)
>>> sleep 1
>>> wait $!
>>> echo done
> 
> I wonder why wait $! doesn't do the job here.

Because `echo "$line" &` sets a new value for $! after the <() did.

More to the point, you want to wait $! *before* running any commands in
the while loop, because if the <() failed, it might not be a good idea
to run those commands.

-- 
Eli Schwartz
Arch Linux Bug Wrangler and Trusted User

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Re: process substitution error handling Eli Schwartz <eschwartz@archlinux.org> - 2020-08-06 13:09 -0400

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