Really old sh -- pipefail

[Richard Laager]

I just tested in dash, which is a minimal sh that does not support 
pipefail. That code works as written and does not work without the ().

I believe the () spawns a subshell generally.

On 2026-09-09 06:16, Hal Murray via devel wrote:
> 
> I'm trying to understand this code from tests/option-tester.sh
> 
> # set pipefail to catch pipeline failures
> # Unfortunately, it doesn't work on some older sh-es
> if (set -o pipefail) 2>/dev/null
> then
>    set -o pipefail
> fi
> 
> What is the () doing there?  Why not just set it and ignore the error if
> that doesn't work?
> 
> I no longer have any systems that are old enough to have a sh that doesn't
> support pipefail.
> 
> Does anybody have an old sh to experiment with?
> 
> 


-- 
Richard