Perl could certainly use a hook triggering before exec(). Performing custom setup between fork() and exec() is essential for correct operation in many scenarios. For example: thread save calling an external command, Re^6: Capture::Tiny alternative.

So the IPC modules might use constructs like 

{
    local $SIG{__EXEC__} = \&_do_redirect;
    system ...
}

[download]
But this would no doubt have other creative uses. Syntactic sugar to make things neat. 
{
    use redirect qw( 3>&1 1>&2 2>&3 3>&- );
    open my $fh, ...;
    `another cmd`;
}

[download]

ps. I'm not entirely sure if the hook ought to be post-fork or pre-exec.

In reply to Re: Improve pipe open? (redirect hook) by oiskuu
in thread Improve pipe open? by afoken

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