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From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@cse.psu.edu
Subject: [9fans] p9p qid.vers for directories
Date: Fri,  9 Dec 2005 10:30:48 -0600	[thread overview]
Message-ID: <20051209163048.816F61C8E5A@dexter-peak.quanstro.net> (raw)

there are several places in p9p where the code depends on this
sort of code:

	if (!(oldqid.path = newqid.path && qid.vers == newqid.vers))
		process_changed_directory();

however on solaris and linux, qid.vers is always zero and qid.path depends
only on the device and inode. so if i cd $dir ; touch newfile this test

	oldqid.path = newqid.path && qid.vers == newqid.vers

evaluates to zero.

what i would like to do is modify _p9dir to do something with 
qid.vers, at least for directories. it doesn't seem as if there's an easy
way to get at the file version¹  out of the linux kernel, though there
are some patches floating around for linux 2.4. i was thinking that
perhaps using the directory mtime or ctime would be a good start.

any ideas?

- erik

¹ file versions are mantained at least reiserfs /usr/include/linux/reiserfs_fs.h:912 
on linux 2.6.14.


             reply	other threads:[~2005-12-09 16:30 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-12-09 16:30 erik quanstrom [this message]
2005-12-09 16:30 erik quanstrom

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