From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <017e01c3134d$66024460$3f00a8c0@MERCURY>
From: "Andrew Simmons" <andrew.simmons@monitorbm.co.nz>
To: <9fans@cse.psu.edu>
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Subject: [9fans] Qid path generation
Date: Tue,  6 May 2003 09:29:23 +1200
Topicbox-Message-UUID: 9e786e42-eacb-11e9-9e20-41e7f4b1d025

I'm pondering how to generate unique qid paths for NTFS/FAT32 files. The 2nd
ed toolset for Windows has a function called "pathqid" which generates a 4
byte number from the filename. I'd appreciate any hints on the workings of
this function, particularly the choice of the magic number 1000003, the
reason for masking with ~CHDIR, and the role of the first parameter, which
always seems to have 0 passed in - plus any ideas on extending the method to
8 bytes, or a better method.

Also, I would guess that a method such as pathqid could occasionally
generate the same number from two different file names. Any guesses as to
the impact of this on a client (eg 9fs)?