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).
OS/2:
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:
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.
