CHGNUM - A Utility To Change Phone Number Library Entries In MODEM9.CMD

         Translated from the 8080 program CHGLIB22 by
           Alex Soya
           P.O. Box 121
           Melbourne Beach, Florida 32951
           (September 20, 1984)

        "Tweaked" to make the program a bit more intuitive by
           Kirk Lawrence (September, 1994)


CHGNUM is a utility which allows you to change entries in the
Phone Number Library, compiled within the MODEM9.CMD program.
CHGNUM is somewhat cumbersome by today's standards, but it
*does* do the job.

    Syntax: CHGNUM input.CMD output.CMD

"input.CMD" represents the current filename of the program (in
this case, "MODEM9.CMD").  "output.CMD" represents a different
filename (of your choice) which will be used to write a new .CMD
file, including the changed entries.  "output.CMD" must be a
filename which does NOT currently exist on the default drive.

What's happening here is that CHGNUM is reading the entire MODEM9.CMD
file into memory, making the changes to the phone number library, and
then writing the entire file, which includes the changed entries, back
to disk with a different filename.  This is an extremely awkward and
unsophisticated way of making such changes, but at least it guarantees
that your original MODEM9.CMD file will remain intact.

When CHGNUM loads the MODEM9.CMD file, it looks for the library of
phone numbers within the first 6000 bytes of the file.  When CHGNUM
finds a section of data that seems to be the library, it displays
that data on the screen, and asks "Is this the library? Y/N."  If
what you see on the screen IS the library of phone numbers, press
"Y."  If by some chance CHGNUM has made an error, and what you see
on the screen is NOT the library of phone numbers, press "N."

Once the "Library of Phone Numbers" is correctly displayed on the
screen, you may use the commands listed below to manipulate the
entries, and then save the changed file.

NOTE: When entering information into the "Library of Phone Numbers,"
each entry must contain EXACTLY 30 CHARACTERS.  If you attempt to
enter either more characters or fewer characters than 30, CHGNUM
will reject your entry, and then prompt you re-enter the information.
A "space" counts as a character, and you may use spaces anywhere
within the entry to "pad," if you so desire.

If you should wish to prematurely exit CHGNUM, pressing CTRL-C will
cleanly abort the program...and any changes which you entered will
not be saved to disk.


SUMMARY OF COMMANDS
~~~~~~~~~~~~~~~~~~~

 Cmd   Syntax    Description
----- --------  -------------
  D      D*       Delete specified entry from library
  H      H        Display "help" screen
  I      I*       Insert new text for specified entry
  P      P        Print full library to printer
  R      R        Re-read library from the source file
  V      V*       View the specified entry on the screen
         V?       View the entire library
  W      W        Write the new .CMD file (with the changed entries) to disk

  "*"  represents one letter, A through Z,
       signifying the entry you wish to work with.