┴ FILE IS A COLLECTION OF INFORMATION HELD IN SOME SEQUENCE THAT MAKES SENSE TO YOU. ┘OU CAN THINK OF A FILE AS A SECTION OF AN OFFICE FILE CABINET DEALING WITH ONE SUBJECT. ┴ DISK OR TAPE CAN HOLD MANY FILES UNDER DIFFERENT NAMES. ┼ACH FILE, IN TURN, CAN CONTAIN MANY FOLDERS OF INFORMATION ABOUT A SMALL SUBJECT, EACH FOLDER CAN BE CALLED A RECORD WITHIN A FILE. ┴ RECORD CAN BE SUBDIVIDED INTO FIELDS, THE SMALLEST PIECES OF INFORMATION. ╙O, TO RECAPITULATE, LET'S USE AN EXAMPLE OF A MAILING LIST FILE:
╞ILE NAME: ═┴╔╠ ╠╔╙╘
╥ECORD 1: PERSON 1
╞IELDS: NAME ADDRESS CITY ZIP-CODE PHONE
╥ECORD 2: PERSON 2
╞IELDS: NAME ADDRESS CITY ZIP-CODE PHONE
... ETC
╘HERE ARE COMMANDS IN THE MANUAL THAT SHOW HOW TO KEEP FILES IN GOOD ORDER. ╘HIS CHAPTER WILL EMPHASIZE SOME POINTS. ╘HE KEY PURPOSE OF THIS CHAPTER IS TO SHOW THE MECHANICS OF WRITING FILES: THE ┬┴╙╔├ KEYWORDS USED AND THE WAY OF SEPARATING FIELDS AND RECORDS SO THAT SUBSEQUENT READING WILL WORK. ╘HIS CHAPTER DOES NOT SHOW WHAT GOES INTO DESIGNING A FILE FROM A LOGICAL POINT OF VIEW. ╘HESE ARE NON-PROGRAMMING ASPECTS OF FILING, HENCE BEYOND THE SCOPE OF THE BOOK. ╘HEY ARE, BY THE WAY, MOST IMPORTANT, AND YOU SHOULD THINK CAREFULLY, BEFORE DOING ANY CODING. ┴SK YOURSELF WHAT IT IS THAT YOU WANT TO FILE, AND HOW IT SHOULD BE ORGANIZED.
├OMMODORE'S FILING SCHEMES ARE QUITE POWERFUL. ╘HERE ARE ╙┼╤╒┼╬╘╔┴╠ FILES (WRITTEN AND READ IN THE SAME ORDER, NO SKIPPING, NO HOPPING), ╥┼╠┴╘╔╓┼ FILES (WRITTEN AND READ IN ANY ORDER, GIVING EXTREMELY FAST ACCESS TO ANY RECORD), ╥┴╬─╧═ FILES (A RELIC FROM THE PAST, DO ╬╧╘ USE THEM, THEY ARE TOO DIFFICULT AND ╥┼╠┴╘╔╓┼ FILES WORK BETTER). ╙EQUENTIAL FILES ARE EASIEST TO WORK WITH AND DO MOST OF THE SMALL JOBS RIGHT. ╘HIS CHAPTER WILL CONCENTRATE ON SEQUENTIAL FILES, AND OVERALL DISK MAINTENANCE, BUT WILL ALSO GIVE A PROJECT FOR LEARNING ABOUT ╥┼╠┴╘╔╓┼ FILES. ╔F YOU'RE INTERESTED IN THAT, THE PROJECT WILL ALLOW YOU TO SEE WHAT MAKES THEM TICK. ╔T WILL BE UP TO YOU TO DRAW YOUR OWN CONCLUSIONS FOR THE BEST USE.
╘HE FORMAT OF PRESENTING INFORMATION IN THIS SECTION DIFFERS FROM PREVIOUS SECTIONS. ╔T WOULD BE SILLY TO DESCRIBE VARIABLES, INSTRUCTIONS AND SO ON, WHEN THE WHOLE TOPIC OF FILING CAN BE HANDLED USING ONE OR TWO VARIABLES. ╫HAT IS IMPORTANT IN LEARNING FILING IS THE PROCEDURES AND PITFALLS TO AVOID. ╚ENCE WHAT FOLLOWS ARE ROUTINES THAT DO ALMOST NOTHING OTHER THAN DEMONSTRATE AND LET YOU PLAY WITH MODIFYING THE CODE UNTIL YOU LEARN WHAT FILING IS ALL ABOUT.
