Jim Kerr - Alaska Juggler
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  File Systems and Names, what little I know

The following begins to summarize naming conventions for files on the various systems - please e-mail me with the missing pieces if you are so inclined. It would be much appreciated.
Windows 95/98/2000/XP:
System CaseSensitive Allowed Charset ReservedChars Reserved Words MaxLength Comments

Win95 VFAT is a case-insensitive file system that reserves |\?*<":>+[]/ as special characters as as control characters and imposes a at limit of 255 characters.
WinXP NTFS has case sensitivity as an optional and reserves |\?*<":>/ as well as control characters and the control workds aux, con, prn as special. It restricts names to be no longer than 260 characters.
WinXP HPFS is case-insensitive but allows case-preservation and reserves the characters |\?*<":>/ while imposing a 254 maximum length on files.
How does DOS figure in?
In general Long names limited to 256 characters, unlimited number of periods. No +,, = , or [ ] are allowed. The first six characters of the name, and first three characters behind the last period will be used to create an alias entry that conforms to the DOS file naming rules, and will contain a ~n as the last of the 8 characters before the file extension. The ~ is literal, and the n represents a number that will make the file name unique.
example: This.Is.A.Wierd.Name will be represented as a label reading THISIS~1.NAM
Later creation of This.Is.A.Really.Weird.Name will yield an alias file label of THISIS~2.NAM. If you want to preserve your own numbered versions of a file, you must place the number either in the first six characters of the file name, or in the first three after the last period for this to show up in the file listings.
All DOS and Windows eol character: (CR, ASCII 13; followed by LF, ASCII 10).
File naming in OS/2 depends on whether the file directory driver is configured for the FAT
(File Allocation Table) or HPFS (high performance file system) formats.
FAT format is the standard 8.3 (DOS) file name space. However, it differs from the list of Windows ‘95 unsupported characters. The following characters are not supported in OS/2 8.3 format: “ / \ : * ? | < > + , ; = [ ] .
Also, in case you were by coincidence thinking of using the following for filenames, they are unusable: KBD$ , PRN, NUL, COM1, COM2, COM3, COM4, CLOCK$, LPT1, LPT2, LPT3, CON, SCREEN$, POINTER$, and MOUSE$.
HPFS format uses up to 254 characters (vs Windows 95 with 255), and may contain any number of periods. All the unsupported characters listed for the FAT format are also unsupported in HPFS. Extended file attributes in HPFS will not appear if files are copied to floppy disk, until they are recopied to an HPFS-formatted hard drive.
DOS applications may not preserve the extended attributes(i.e. long file names) of HPFS!
eol character: (CR, ASCII 13, LF, ASCII 10).

OS/9 and earlier Macintosh
Macintosh recognizes file names up to 31 characters, no apparent restriction on character types. Just be aware that if transferring to Windows ‘95 file system, the above-listed restrictions apply to Mac file names also (i.e. unsupported characters). When backing up VAX files to a Mac file server, the trailing ; and version number get truncated.
eol character: (CR).
Mac OS X HFS+ case-insensitive and preserves case. At the Unix layer things are Unix; Carbon layer rules apply to that lever. There is a 255 name limit imposed

UNIX (and Machitosh OS/10
eol character: line feed (LF, ASCII 10)
VAX filenames may be up to 39 characters in length, followed by a period and up to another 39 characters. The only three supported non-letter characters are $ , - , and _ .
If backing up files to Windows ‘95 derived via FTP, mail, etc, it will be necessary to eliminate the trailing semicolon, and - if you want to save the version number- move that into the first six characters of the filename.
eol character: (LF, ASCII 10; followed by CR, ASCII 13, ).
System CaseSensitive Allowed Charset ReservedChars Reserved Words MaxLength Comments
MS-DOS FAT case-insensitive case-destruction A-Z,0-9,-,_ all except allowed 12
Commodore 64 case-sensitive case-preservation any " 16 Flat filesystem with no subdirs. Space and shift-space are different chars.

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