Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!gatech!bloom-beacon!apple!mattd
From: mattd@Apple.COM (Matt Deatherage)
Newsgroups: comp.sys.apple
Subject: Re: P8, lowercase & Sys Disk 5.0
Message-ID: <31256@apple.Apple.COM>
Date: 21 May 89 19:39:30 GMT
References: <8905182336.AA05791@crash.cts.com>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 43

In article <8905182336.AA05791> pnet01!pro-sol!mdavis@nosc.mil writes:
>Network Comment: to #7251 by pnet01!crash!apple.com!dlyons
>
>> you just get a file-already-exists error, and the old capitalization
>> is retained.  Not sure if this is the most reasonable behavious or
>> not...
>
>Mac HFS won't allow two files to share the same name (regardless of upper or
>lower case).  If you have a file called "OOGA" and try to create a new file
>called "Ooga", the Mac will complain.  I guess the GS/OS designers are just
>following what the Mac does.

Cheap shot, Morgan.  The ProDOS FST will not allow files with the same names
but different capitalization because ProDOS 8 does not know about lower-case
file names.  The file names in the directory are all upper-case, like they
always have been, and the "version/minversion" bytes have been redefined to
be case bits.  

If the FST allowed the same file name, P8 would find two files in the directory
with the same name, as far as it's concerned.  It would then either return
"duplicate file name" errors where inappropriate, or would never find the
second one in the directory entry.  Not to mention that since there is no
P8 "GetDirEntry" call, anyone who accepts file name input in upper and lower
case has to translate it to upper case before searching the directories (under
ProDOS 8), so storing the names in lower case in the directory entry would 
similarly cause them to be mostly inaccessible.

The case bits/no duplicates is a close-to-happy compromise which allows ProDOS
8 to use the files while allowing the ProDOS FST to keep the names in upper
and lower case (which is an FST-specific option that can be turned off, if
your program wants to do so).  Expanding the file system in this way isn'
always possible (see the discussion on forked files).


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