Talk:Disc Filing System

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This is to "83.67.106.202" (!) -- you say that "|" is not allowed in filenames because it is a shell escape. Please provide an example? (Or anyone who is reading this). MOS 3 allows you to construct control characters like |S for ctrl-S, but when the DFS came out, we were not at MOS 3 yet and this was not a feature that existed. So what did | do at the time? Ghiraddje 21:46, 16 May 2007 (UTC)

MOS 1.20 (model B) also had the control character generator - you could use it in *KEY commands for example. The Disc Filing System User Guide p.21 says any character can be used except * # : . but since the DFS uses GSREAD internally, the | character is special. Acorn DFS 1.20 rejects SAVE "FO|O" with a 'Bad name' error, but SAVE "FO||O" results in a file named FO|O, which can be loaded back with LOAD "FO||O". You can also do SAVE "||||||||||||||" as the resulting filename has only seven characters. In practice, only printable characters appeared in file names, though a lot of PD discs used Teletext characters in their titles. (FWIW | has another unrelated function of starting comments, e.g. *| This is a comment.) HTH -- Regregex 13:24, 1 August 2007 (UTC)

"GSREAD"? Ghiraddje 23:16, 1 August 2007 (UTC)

A pair of routines in the MOS for processing strings. Not documented by Acorn, but used by BASIC, DFS and some third party applications. The unofficial Advanced User Guide (1983, PDF) gave details on pp.105-6. -- Regregex 11:52, 2 October 2007 (UTC)

Thanks for the information! (Also lovely to see the entire Advanced User Guide OCRed and even set in the correct font) Ghiraddje 01:09, 4 October 2007 (UTC)

[edit] Acorn System DOS

Wasn't Acorn DFS based on the filing system used in the System series? IIRC there was a DCONV utility on the DFS Welcome disc to strip the BBC Micro extensions from the catalogue so the disc could be used in System series machines. -- Regregex 13:33, 1 August 2007 (UTC)