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From: Miles Chen <miles.chen@mediatek.com>
To: <masahiroy@kernel.org>
CC: <corbet@lwn.net>, <jonathanh@nvidia.com>, <linux-doc@vger.kernel.org>,
	<linux-kbuild@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
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Subject: Re: [PATCH v3] scripts/check-local-export: avoid 'wait $!' for process substitution
Date: Sat, 11 Jun 2022 00:57:24 +0800
Message-ID: <20220610165724.16214-1-miles.chen@mediatek.com>
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>Bash 4.4, released in 2016, supports 'wait $!' to check the exit status
>of a process substitution, but it seems too new.
>
>Some people using older bash versions (on CentOS 7, Ubuntu 16.04, etc.)
>reported an error like this:
>
>  ./scripts/check-local-export: line 54: wait: pid 17328 is not a child of this shell

Thanks for fixing this!
I hit this issue and this patch fixes my problem.

Tested-by: Miles Chen <miles.chen@mediatek.com> 

>
>I used the process substitution to avoid a pipeline, which executes each
>command in a subshell. If the while-loop is executed in the subshell
>context, variable changes within are lost after the subshell terminates.