Scratch; Initialize; Validate - Commodore 1541 User Manual

SCRATCH
This command allows you to erase unwanted files and programs from the disk,
which then makes the blocks available for new information. You can erase programs
one at a time or in groups by using pattern matching and or wild cards.
FORMAT FOR SCRATCH COMMAND
PRINT# 15, "SCRATCH:name"
or abbreviated as
PRINT# 15, "S:name"
If you check the error channel after a scratch operation (see below), the number
usually reserved for the track number now tells you how many files were scratched. For
example, if your directory contains the programs KNOW and GNAW, and you use the
command PRINT# 15, "S:?N?W", you will scratch both programs. If the directory
contains TEST, TRAIN, TRUCK, and TAIL, and you command the disk to PRINT#
15, "S:T*", you will erase all four of these programs.
INITIALIZE
At times, an error condition on the disk will prevent you from performing some
operation you want to do. The INITIALIZE command returns the disk drive to the
same state as when powered up. You must be careful to re-match the drive to the com
puter (see chapter 2).
FORMAT FOR INITIALIZE COMMAND:
PRINT# 15, "INITIALIZE"
or abbreviated as
PRINT# 15, "I"
VALIDATE
After a diskette has been in use for some time, the directory can become
disorganized. When programs have been repeatedly SAVEd and SCRATCHed, they
may leave numerous small gaps on the disk, a block here and a few blocks there. These
blocks never get used because they are too small to be useful. The VALIDATE com
mand will go in and re-organize your diskette so that you can get the most from the
available space.
Also, there may be data files that were OPENed but never properly CLOSEd.
This command will collect all blocks taken by such files and make them available to the
drive, since the files are unusable at that point.
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