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To: Ed Schouten <ed@nuxi.nl>
cc: Konstantin Belousov <kostikbel@gmail.com>,
 FreeBSD Hackers <freebsd-hackers@freebsd.org>,
 Dimitry Andric <dim@freebsd.org>, Thomas Munro <munro@ip9.org>
Subject: Re: printf("%m") doesn't generate a warning -- shouldn't it?
In-reply-to: <CABh_MKkWOaKZxqye2zW7tGF2Pro6hvnf5PHTgY8HqtHrFCprqg@mail.gmail.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
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Date: Tue, 22 May 2018 09:37:18 +0000
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--------
In message <CABh_MKkWOaKZxqye2zW7tGF2Pro6hvnf5PHTgY8HqtHrFCprqg@mail.gmail=
.com>
, Ed Schouten writes:
>2018-05-21 15:43 GMT+02:00 Konstantin Belousov <kostikbel@gmail.com>:
>> Why not add %m instead ?  It is very easy and several people did it in
>> round-about ways.
>
>Added advantage of that approach is that it allows the syslog()
>function to be simplified significantly. No need to expand the %m
>there, which ends up being quite messy.

We have an cleanly expandable printf implementation for exactly
this kind of stuff, so that is not really the case.

However, expandable printf is close to useless when there is no
sane/portable way to teach compilers about new formatting arguments.

-- =

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    =

Never attribute to malice what can adequately be explained by incompetence=
.