The second of our brace of disk books is by Ian Sinclair. It is larger than the first, enclosing 114 pages. As a bonus there is also a section on printers. In common with the previous work, the book starts with a description of the hardware and floppies, including the layout of tracks and sectors.

The LOAD, SAVE and VERIFY commands are illustrated with the use of the games disk, currently supplied free with the 1541. No mention is made of the bug reported by Hetherington and Hamlett. A short subroutine to read the error channel is included, together with a useful tip on how to load the disk directory without overwriting the program in memory.

Hexadecimal notation is clearly explained so that you can use the DISPLAY T&S program included on page 49 of the Commodore manual. Backup procedures lead logically to the file handling commands COPY, SCRATCH, etc. together with the advantages of wildcards and pattern matching.

The above mentioned games disk contains a BACKUP program, without any documentation! Mr. Sinclair makes up for this deficiency by including instructions to this and the programs listed in the back of the 1541 manual. These gems are priceless.

The concept of files is introduced generally, and concentrates on Serial files specifically. Short subroutines are used to demonstrate reading, and extending a Serial file. Random Access files are relegated to an appendix, but Relative files are covered in depth. Again, useful subroutines are listed. The author admits that the routines are only for learning purposes, as a Sequential file is needed to keep track of Relative files.

Unlike the first book, the next chapter carefully and clearly describes a program which creates a simple database. The system uses two Relative and one Serial file. This program may be used as a basis for something more advanced.

The final chapter is devoted to printers, describing the various types available and any interfaces needed. The Epson RX80, Juki 6100, CGP-115 and the now discontinued Commodore 1515 are individually covered. Six appendixes conclude the book.

This book is for beginners. It reads easily and explains everything clearly. Unlike the Hetherington and Hamlett book, it actually gets down to creating a useful filing system, but if you really need Random files, then look elsewhere.