Commodore 128D - Drive Specifier; Filename; Filetype

Drive Specifier
Filename
The drive specifier is a single letter (A-P) fol
lowed by a colon. Each disk drive in your system
is assigned a letter. When you include a drive
specifier as part of the file specification, you are
telling CP/M to look for the file on the disk cur
rently in the specified drive. For example, if you
enter:
B.MYFILE RETURN
CP/M looks in drive B for the file MYFILE. If you
omit the drive specifier, CP/M 3.0 looks for the
file in the default drive (usually A).
A filename can be from one to eight characters
long, such as:
MYFILE
A file specification can consist simply of a
filename. When you make up a filename, try to
let the name tell you something about what the
file contains. For example, if you have a list of
customer names for your business, you could
name the file:
CUSTOMER
so that the name gives you some idea of what is
in the file.
Flletype
To help you identify files belonging to the same
category, CP/M allows you to add an optional
one- to three-character extension, called a file-
type, to the filename. When you add a filetype to
the filename, separate the filetype from the
filename with a period. Try to use letters that tell
something about the file's category. For exam
ple, you could add the following f iletype to the
file that contains a list of customer names:
CUSTOMER.NAM
When CP/M displays file-specifications, it adds
blanks to short filenames so that you can com
pare filetypes quickly. The program files that
CP/M loads into memory from a disk have the
f iletype COM.
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USING CP/M MODE—Files, Disks and Disk Drives in CP/M 3.0