SWEEP TIP: USING THE Y OPTION ...................................... Rick Ryall

     For quite some time I have wondered how to use the NEWSWEEP "Y" option to
change the status of a file, but had been unsuccessful at either figuring it
out myself or locating someone else whoe did. However, the latest issue of
Micro Cornucopia featured excerpts from a talk by none other than the author of
NEWSWEEP himself, Dave Rand, and he explained it.

     Before we learn how to use this feature, though, it is necessary to
briefly go over some background on filenames.  Within the CP/M operating system
a filename consists of a 1 to 8 character name optionally followed by a period
and a 1 to 3 character extent, as in MBASIC.COM, where MBASIC is the name and
COM is the extent.  Without going into a lot of detail, CP/M uses what is
called the "high bit" or "parity bit" of some of the filename characters in
order to flag a file as being of a special type, like a read-only file (which
cannot be easily erased or overwritten) or a system file (which will not appear
in a DIR listing, making it sort of invisible).

     The file status option allows you, the user, to set or reset the file
status in an easy fashion.  What this means is that you can conveniently make
normal read-write files into read-only or invisible files and vice versa, plus
some other things.  The key word here is conveniently, because convenience is
in direct contrast to utilities like STAT which are downright nasty in the
ease-of-use department.

     Here is how to use the file status feature of NEWSWEEP.  When you press
"Y" while using the program, you should get the following prompt:

                           Which flags (1-4,R,S,A)?

The word "flags" is referring to the parity bits of the filename characters.
Choosing 1, 2, 3, or 4 will set the parity bit of the first, second, third, or
fourth filename name characters, respectively, and I have no idea why a person
might want to change the parity bits of these characters, but I am sure there
is a good reason or the feature would not have been included.  Choosing R, S,
or A will set the first, second, or third parity bit of the filename extent
character (the part that follows the period).  The R stands for read-only, the
S for system, and the A for archive (I think).  Choosing anything besides the
seven choices listed will reset all the filename flags, making the file a read-
write file once more.  Below are some examples of responses to the prompt and
what the program would do in each instance.

YOU    WHAT HAPPENS
TYPE

R      Sets the file to read-only status.
S      Makes the file invisible to a directory listing.
1      Sets the flag of the first filename character.
23RS   Sets the 2nd, 3rd, read-only, and system flags.
RA     Sets the read-only and archive flags.
0      Sets the file back to read-write status.

     There is one other thing that you need to know, though, before you attempt
to use this option: it only works on tagged files, so the first step is to tag
all the files that need a change of status, even if you are only changing the
status of one file (this was the part that I could not figure out).  This is a
good thing, because it allows you to set the status of a number of files at
once as long as they are all to be given the same attribute (like read-only).

     If you have a graphics machine, you may notice that the characters
corresponding to the flags you set become highlighted when you set them.  This
highlighting can be used in combination with the "A" flag to aid in backing up
your files because you will be able to see which files have been changed since
the last backup, even if you don't have one of those "date stamper" operating
systems.

     This is how you would do just that.  The first time you back a disk up,
you will need to tag all the files and copy them to the backup disk using the
"M" (Mass copy) option.  When the copy is complete, use the "A" option (Again)
to tag those same files again.  Next, choose the "Y" option to change the file
status of the tagged files, and you will see the prompt "Which flags (1-
4,R,S,A)? ".  Choose "A" (Archive).  After having completed these three steps
on your first backup, all the filenames will have a highlighted last character,
indicating that you have backed them up.  A kind of visual aid.  The next time
that you go to back up your disk, all you need to do is to look for filenames
that do not have the last character highlighted, since these files will have
been created or changed since the last backup (CP/M resets the archive flag
whenever a file is created or changed).  You would then tag them (by hand, that
is, individually) and copy them to the backup disk using the "M" selection
(Mass copy).  When the transfer is complete, use the "A" (Again) option to
retag the files that were just backed up, and then set the archive flags using
the same procedure as described above.