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From: "" <kfm@plushkava.net>
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Subject: Re: process substitution error handling
Date: Thu, 6 Aug 2020 15:26:14 +0100
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On 06/08/2020 14:57, Eli Schwartz wrote:
> On 8/6/20 9:15 AM, kfm@plushkava.net wrote:
>> You beat me to it. I was just about to suggest wait $! || exit. Indeed,
>> I mentioned the same in a recent bug report against wireguard-tools.
> 
> So if I understand correctly, you reported the lack of wait $! || exit
> in a script, and the script author instead responded by requesting a new
> feature in bash that does the same thing, except after a random interval
> during another command's execution?

Well, I wouldn't presume to know whether there is any relationship 
between said report and the feature request under discussion. Briefly, 
the errexit pitfall that affected me can be seen here:

https://github.com/WireGuard/wireguard-tools/blob/v1.0.20200513/src/wg-quick/darwin.bash#L299

I happened to mention that the exit status value of networksetup(8) is 
never checked and that it ought to be, with wait $! being one way of 
doing so. That being said, the proposed solution eschewed the use of 
process substitution altogether.

> 
>> I concur. The scripts I looked at tended heavily towards error handling
>> at a distance and were already subject to one or two amusing errexit
>> pitfalls.
> 
> lol, I bet we could fix that by adding even more error handling at a
> distance.
> 
-- 
Kerin Millar