THE DISK CATALOGUE SYSTEM
=========================

UPDATE NOTES : RELEASE 1.01 - 26th SEPTEMBER 1992

RELEASE 1.01 ENHANCES RELEASE 1.0 BY CORRECTING A NUMBER OF BUGS, PROVIDING
A MORE 'STANDARD' USER INTERFACE AND INCORPORATING MORE ERROR CHECKING.

1) BUG CORRECTIONS :

   A) IN RELEASE 1.0, IF THE USER ENTERED EITHER A FOLDER OR FILENAME WHICH
WAS 13 CHARACTERS LONG (INCLUDING THE STRING NULL TERMINATOR) THEN THE NAME
WAS TRUNCATED AND THE LAST CHARACTER 'DRAGGED' INTO THE NEXT FIELD. THE
TYPE-AHEAD BUFFER THEN PASSED THE REMAINING DATA INTO THE NEXT RECORD,
CAUSING PROBLEMS WHEN THE CODE RECEIVED CHARACTER DATA WHEN IT WAS EXPECTING
AN INTEGER.

   THIS BUG HAS BEEN COMPLETELY ERADICATED.

   B) THE ENTRY OF INTEGERS INTO THE DISK NUMBER AND SUBJECT CODE FIELDS WAS
NOT VALIDATED. THIS LED TO PROBLEMS IF THE ENTRY CONTAINED CHARACTER DATA.

      BOTH FIELDS ARE NOW VALIDATED TO ACCEPT NUMERIC DATA ONLY. THE EXCEPTION
TO THIS IS THAT WHEN ADDING RECORDS A VALUE OF 'Q' AS THE DISK NUMBER ALLOWS
THE USER TO STOP ENTERING RECORDS.

   C) IF THE USER ENTERED AN INVALID FILENAME WHEN DELETING THEN THE PROGRAM
CRASHED. THIS HAS BEEN CORRECTED.

   D) WHEN PACKING A DELETED RECORD FROM THE DATABASE THE CODE WAS MERELY
DUPLICATING THE UN-WANTED RECORD. THIS HAS BEEN CORRECTED. IF YOU HAVE
ALREADY SET UP A DATABASE WITH VERSION 1.0 YOU WILL NEED TO TAKE THE
FOLLOWING STEPS TO CORRECT IT :-

     ** DON'T FORGET TO BACKUP YOUR SYSTEM BEFORE STARTING **

     1. EDIT YOUR DCAT.DTA FILE WITH A TEXT EDITOR WHICH CAN WRITE A PURE
ASCII FILE. SCAN THIS FILE FOR THE RECORDS WHICH YOU HAVE DELETED AND
REMOVE EVERY DUPLICATE ENTRY.

     2. AMEND THE FIRST ENTRY IN DCAT.DTA TO READ THE NUMBER OF DISK RECORDS
IN YOUR CORRECTED DATABASE.

     3. SET THE DELETED INDICATOR ON AT LEAST ONE GOOD RECORD IN YOUR DATABASE
BY CHANGING ITS SUBJECT CODE TO 99.

     4. SAVE DCAT.DTA AS A PURE ASCII FILE.

     5. LOAD DCAT.TOS AND READ IN YOUR DATFILE. SELECT THE OPTION THE REMOVE
DELETED RECORDS. YOUR DATABASE WILL NOW BE REBUILT.

2) STANDARD USER INTERFACE :

   A) ALL OPERATIONS REQUIRING CHOICE OF ACTION NOW ACCEPT 'Y/N' RESPONSES.
IN VERSION 1.0 BOTH 'Y/N' AND '1/2' SELECTORS WERE USED.

   C) IN VERSION 1.01 WHEN BOTH ADDING OR AMENDING RECORDS, ENTERING 'Q' AS
THE DISK NUMBER ABORTS THE OPERATION.

3) ENHANCED ERROR CHECKING :

   A) WHEN THE OPTION IS SELECTED TO QUIT DCAT.TOS, THE USER MUST POSITIVELY
AUTHORISE THE ACTION. THIS PREVENTS THE USER FROM INADVERTANTLY QUITTING
FROM THE PROGRAM BEFORE HAVING SAVED THE LATEST DATA FILE.

   B) BOTH DISK NUMBER AND SUBJECT CODE ARE VALIDATED TO ENSURE THEY ARE
NUMERIC. SUBJECT CODE IS FURTHER VALIDATED TO ENSURE THAT IT RANGES 1 - 9.

4) ENHANCEMENTS :

   A) IN VERSION 1.0 THE USER HAD TO SELECT THE ADD OPTION FROM THE MAIN MENU
EACH TIME A RECORD WAS TO BE ADDED TO THE DATABASE. IN VERSION 1.01 THE USER
MAY ADD CONSECUTIVE RECORDS.

   B) AS NOTED ABOVE, THE USER MUST CONFIRM HIS/HER REQUEST TO EXIT FROM
DCAT.TOS.

5) FUTURE DEVELOPMENT :

   FOR THE NEXT RELEASE I AM LOOKING TO FURTHER INCREASE THE 'FEEL' OF THIS
PROGRAM IN TWO WAYS. I AM FIRSTLY HOPING TO BE ABLE TO PROVIDE A GEM
INTERFACE TO MAKE USAGE MORE INTUITIVE. SECONDLY, I HOPE TO BE ABLE TO
PROVIDE ON-SCREEN DISPLAY OF SUBJECT CODE DEFINITIONS WHEN ADDING OR
AMENDING RECORDS.

L.J. RUSSELL, 26th SEPTEMBER, 1992