Commodore 1581 - Renaming and Scratching Troublesome Files

RENAMING AND SCRATCHING TROUBLESOME FILES
Eventually, you may run across a file which has an odd filename,
such as a comma by itself (",") or one that includes a Shifted Space (a
Shifted Space looks the same as a regular space, but if a file with a
space in its name won't load properly and all else is correct, it's
probably a Shifted Space). Or perhaps you will find one that includes
nonprinting characters. Any of these can be troublesome. Comma
files, for instance, are an exception to the rule that no two files can
have the same name. Since it shouldn't be possible to make a file
whose name is only a comma, the disk never expects you to do it
again.
Files with a Shifted Space in their name can also be troublesome,
because the disk interprets the Shifted Space as signaling the end of
the file name, and prints whatever follows after the quotation mark
that marks the end of a name in the directory. This technique can be
useful by allowing you to have a long file name, and making the disk
recognize a small part of it as being the same as the whole thing
without using pattern-matching characters.
In any case, if you have a troublesome filename, you can use the
CHR$() function to specify troublesome characters without typing
them directly. This may allow you to build them into a RENAME
command. If this fails, you may also use the pattern-matching charac
ters in a SCRATCH command. This gives you a way to specify the name
without using the troublesome characters at all, but also means loss of
your file.
For example, if you have managed to create a file named ""MOV
IES", with an extra quotation mark at the front of the file name, you
can rename it to "MOVIES" using the CHR$() equivalent of a quotation
mark in the RENAME command:
I PRINT#15,uR0:MOVIES = " + CHR$(34) +"MOVIES"
The CHR$(34) forces a quotation mark into the command string
without upsetting BASIC. The procedure for a file name that includes a
Shifted Space is similar, but uses CHR$(l60).
In cases where even this doesn't work, for example, if your
diskette contains a comma file, (one named ",") you can get rid of it
this way:
PRINT#15,"S0:?"
This example deletes all files with one character names.
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