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From: Rich Felker <dalias@libc.org>
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Subject: Re: Re: posix_spawn
Date: Mon, 30 Sep 2019 22:21:02 -0400
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On Mon, Sep 30, 2019 at 06:58:15PM -0700, Joshua Hudson wrote:
> Well that was a long dead end. posix_spawnp won't call setgroups.

In a worst case, you use a helper executable (or shell script) to exec
the final program you want running as the child with the changes you
want made to its initial execution environment. This can work around
any deficiency in posix_spawn capabilities. It adds a little bit of
cost but it's nowhere near as big as the cost of fork duplicating the
whole VM space and making it all COW.

> You now have a quirk and I need to actually detect musl libc.

Huh? This does not sound musl-specific.

Rich