[462] in bugtraq
Re: Race conditions, mkstemp (fwd)
daemon@ATHENA.MIT.EDU (Jonathan M. Bresler)
Sun Dec 11 13:58:03 1994
Date: Sun, 11 Dec 1994 12:20:29 -0500 (EST)
From: "Jonathan M. Bresler" <jmb@kryten.Atinc.COM>
To: casper@fwi.uva.nl
Cc: bugtraq@fc.net
On Sun, 11 Dec 1994, Casper Dik wrote:
>
> >
> > here is the source for mkstemp from csrg. note the filesystem
> >must support exclusive file locking atomic to the open() for this to be
> >helpful. as is written in the mkstemp() man page.
> >
> > why wasnt O_TRUNC included. that would hammer both soft and hard links
>
>
> Because it serves no useful purpose. A file created with O_EXCL|O_CREAT
> will have 0 lenght. If the file needs to be truncated (O_TRUNC) it
> already exists, but i that case the open w/ O_CREATE|O_EXCL would fail.
>
> O_CREATE|O_TRUNC|O_EXCL makes no sense.
>
> Casper
>
i gotta learn to read the man pages more carefully. there it si
at the bottom, in plain view:
[EEXIST] O_CREAT and O_EXCL were specified and the file exists.
sorry for wasting everyone's time.
jmb
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