Advanced Disc Filing System: Difference between revisions

Revision as of 14:08, 14 October 2019

Revision as of 13:51, 11 February 2020

Line 26:

|OS = [[Acorn MOS]], [[RISC OS]]

}}

The '''Advanced Disc Filing System''' ('''ADFS''') is a computing [[file system]] particularunique to the [[Acorn Computers Ltd|Acorn]] computer range and [[RISC OS]]-based successors. Initially based on the rare Acorn Winchester Filing System, it was renamed to the Advanced Disc Filing System when support for [[floppy discsdisc]]s was added (utilisingusing a WD1770 floppy disc controller) and on later [[32-bit]] systems a variant of a PC-style floppy controller.<ref>{{cite web|url=http://chrisacorns.computinghistory.org.uk/docs/Acorn/Manuals/Acorn_ADFSUG.pdf |format=PDF |title=Advanced Disc Filing System : User Guide |website=Chrisacrons.computinghistory.org.uk |accessdate=2016-08-01}}</ref>

Acorn's original [[Disc Filing System]] was limited to 31 files per disk surface, 7 characters per file name and a single character for directory names, a format inherited from the earlier Atom and System 3–5 [[Eurocard (printed circuit board)|Eurocard]] computers. To overcome some of these restrictions Acorn developed ADFS. The most dramatic change was the introduction of a hierarchical directory structure. The filename length increased from 7 to 10 letters and the number of files in a directory expanded to 47. It retained some superficial attributes from DFS; the directory separator continued to be a dot and <code>$</code> now indicated the hierarchical root of the filesystem. <code>^</code> was used to refer to the parent directory, <code>@</code> the current directory, and <code>\</code> was the previously-visited directory.