Path: utzoo!censor!geac!torsqnt!jarvis.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!unido!laura!klute@heike.informatik.uni-dortmund.de
From: klute@heike.informatik.uni-dortmund.de (Rainer Klute)
Newsgroups: comp.sys.atari.st
Subject: Folder hierarchy and pathname length
Message-ID: <2018@laura.UUCP>
Date: 26 Feb 90 08:31:12 GMT
References: <2051@atari.UUCP>
Sender: news@laura.UUCP
Reply-To: klute@heike.informatik.uni-dortmund.de (Rainer Klute)
Organization: University of Dortmund, W-Germany
Lines: 34

In article <2051@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes:
>Most people don't open a file 40 directories down in
>their heirarchy, or two folders each 20 (different) levels down, or
>whatever.

Hmm, is that really possible? I once tried out how deep a file
could be nested in the file system hierarchy. From the desktop
I created a folder "1" in the root directory, then a folder "2"
within "1" and so on. I ended with folder "8" and got a message
which told me that it is not possible to create a folder so
deep in the index structure. To open a file 20 or 40 levels
deep in the file system should not be possible.

Now you can calculate the maximum pathname length: 3 (drive id,
colon, backslash) + 8 (max. folder nesting) * (8+1+3+1)
(basename (folder), dot, extension, backslash) + (8+1+3)
(basename (file), dot, extension) + 1 (string terminating null
character) = 120.

Many (most?) programs do not care for pathnames of that length.
For example I got 1st Word Plus to bomb out when I tried to
open a file "D:\11111111.111\...\88888888.888\TEST.DOC".
Probably the internal pathname buffer is to small and longer
names overwrite other data. My Laser C documentation says that
a 64 byte buffer for the dirname portion of a pathname is
sufficient. However, I do not know what the official Atari
developer's documentation says.

Any comments?

  Dipl.-Inform. Rainer Klute      klute@heike.informatik.uni-dortmund.de
  Univ. Dortmund, IRB             klute@unido.uucp, klute@unido.bitnet
  Postfach 500500         |)|/    ...uunet!mcvax!unido!klute
D-4600 Dortmund 50        |\|\    Tel.: +49 231 755-4663