bug#64735: 29.0.92; find invocations are ~15x slower because of ignores

[Eli Zaretskii]

> From: Ihor Radchenko <yantar92@posteo.net>
> Cc: sbaugh@catern.com, sbaugh@janestreet.com, dmitry@gutov.dev,
>  michael.albinus@gmx.de, rms@gnu.org, 64735@debbugs.gnu.org
> Date: Sun, 23 Jul 2023 13:56:35 +0000
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Anything's possible, but when a function produces text, like file
> > names, then the natural thing is either to return them as strings or
> > to insert them into some buffer.
> 
> Do you mean to re-use process buffer and process API, but for internal
> asynchronous C functions (rather than sub-processes)?

Not necessarily a process buffer, no.  Just some temporary buffer.  We
already do stuff like that for some C primitives.