linux-kernel - Re: adding proper O_SYNC/O_DSYNC, was Re: O

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20090828165049.GC8036@shareable.org>
Date:	Fri, 28 Aug 2009 17:50:49 +0100
From:	Jamie Lokier <jamie@...reable.org>
To:	Christoph Hellwig <hch@...radead.org>
Cc:	Ulrich Drepper <drepper@...hat.com>, linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: adding proper O_SYNC/O_DSYNC, was Re: O_DIRECT and barriers

Jamie Lokier wrote:
> That's because this thread is the first time I've heard that Linux
> O_SYNC was really the weaker O_DSYNC in disguise, and judging from the
> many Googlings I've done about O_SYNC in applications and on different
> OS, it'll be news to other people too.
> 
> (I always thought the "#define O_DSYNC O_SYNC" was because Linux
> didn't implement the weaker O_DSYNC).

It looks like we're not the only ones.  AIX has:

http://publib.boulder.ibm.com/infocenter/systems/index.jsp?topic=/com.ibm.aix.genprogc/doc/genprogc/fileio.htm

    Before the O_DSYNC open mode existed, AIX applied O_DSYNC semantics to
    O_SYNC. For binary compatibility reasons, this behavior still
    exists. If true O_SYNC behavior is required, then both O_DSYNC and
    O_SYNC open flags must be specified. Exporting the XPG_SUS_ENV=ON
    environment variable also enables true O_SYNC behavior.

-- Jamie
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/