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From: Eli Zaretskii <eliz@gnu.org>
Newsgroups: gmane.emacs.bugs
Subject: bug#46881: 28.0.50; pdumper dumping causes way too many syscalls
Date: Fri, 05 Mar 2021 09:19:00 +0200
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 (message from Pip Cet on Fri, 5 Mar 2021 02:30:13 +0000)
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> From: Pip Cet <pipcet@gmail.com>
> Date: Fri, 5 Mar 2021 02:30:13 +0000
> Cc: Eli Zaretskii <eliz@gnu.org>, Paul Eggert <eggert@cs.ucla.edu>, 46881@debbugs.gnu.org
> 
> > It looks fine, but wouldn't dumping to a FILE* (with internal buffering)
> > do the same basic thing in a simpler way?
> 
> I initially set out to do that, but decided against it. We don't just
> write sequentially (when FILE I/O helps, a little), we also have the
> seek-and-fixup phase, and it didn't seem any simpler at that point..

I'm not sure I understand: what's wrong with fseek?