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From: Rich Felker <dalias@libc.org>
To: musl@lists.openwall.com
Subject: Re: [musl] Why connect() in syslog?
Date: Fri, 6 Nov 2020 16:44:20 -0500	[thread overview]
Message-ID: <20201106214420.GZ534@brightrain.aerifal.cx> (raw)
In-Reply-To: <20201106193050.GB2009@voyager>

On Fri, Nov 06, 2020 at 08:30:50PM +0100, Markus Wichmann wrote:
> Hi all,
> 
> I was reading musl's syslog source code today for unrelated reasons, and
> saw that it is using connect() to set the destination. And it has some
> code to deal with connection failures. But why? I see the syslog socket
> is a datagram socket, so I thought sendto() with destination address
> means the same thing as connect() and send(), with the difference that
> it is one less syscall that can fail and no connection errors to handle.
> I tried finding information about the semantics of connect() on a UNIX
> datagram socket, but failed to find anything useful.

It's there so the process can chroot, move into a namespace/container,
etc. after calling openlog without losing the ability to do logging.

Rich

      reply	other threads:[~2020-11-06 21:44 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-06 19:30 Markus Wichmann
2020-11-06 21:44 ` Rich Felker [this message]

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