Commodore 1581 - Verify Command

danger a disaster such as losing power midway through the process
would destroy both the old and hew copies of the file. Nothing
happens to the old copy until after the new copy is saved properly.
VERIFY
The VERIFY command can be used to make certain that a pro
gram file was properly saved to disk. It works much like the LOAD
command, except that it only compares each character in the program
against the equivalent character in the computer's memory, instead of
actually being copied into memory.
If the disk copy of the program differs even a tiny bit from the
copy in memory, "VERIFY ERROR" will be displayed, to tell you that
the copies differ. This doesn't mean either copy is bad, but if they were
supposed to be identical, there is a problem.
Naturally, there's no point in trying to VERIFY a disk copy, of a
program after the original is no longer in memory. With nothing to
compare to, an apparent error will always be announced, even though
the disk copy is automatically verified as it is written to the diskette.
FORMAT FOR THE VERIFY COMMAND:
VERIFY "drive#:pattern",device#,relocate flag
where "drive#:" is an optional drive number, "pattern".is any string
expression that evaluates to a file name, with or without pattern-
matching characters, and "device#" is the disk device number, nor
mally 8. If the relocate flag is present and equals 1, the file will be
verified where originally saved, rather than relocated into the BASIC
text area.
A useful alternate form of the command is:
VERIFY"*",device #
It verifies the last files used without having to type its name or drive
number. However, it won't work properly after SAVE-WITH-REPLACE,
because the last file used was the one deleted, and the drive will try to
compare the deleted file to the program in memory. No harm will
result, but "VERIFY ERROR" will always be announced. To use VERIFY
after @SAVE, include at least part of the file name that is to be verified
in the pattern.
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