!pr1
Changing VERIFY to DISPLAY.................Bob Sander-Cederlof

In the July 1982 issue of AAL we showed how to make a text file display command inside DOS.  Bob Bragner added 80-column display to it in the July 1983 issue.  The Dec 1983 InCider printed an article by William G. Wright about a DOS modification that provided text file display without removing any previous features.

Wright's patches modify the VERIFY command so that as sectors are being verified, if the file is a text file, they are displayed on the screen or printer.  If there are any $00 bytes in a sector, they are merely skipped over, so his patches will handle some random access files, as well as sequential.  Non-text files are still verified in the normal manner.

I was prompted by his article to write ukp another little program.  This one will hook into the VERIFY processor in the file manager when you BRUN the program.  Later, 30BG from the monitor or CALL 779 from Applesoft will dis-install the patch.  My patch modifies VERIFY so that as each sector of a file is verified it is displayed in hexadecimal on the screen or a printer.  I do not distinguish between text and non-text files, although it would be a simple matter to do so.  As with Wright's patches, random access files may also be displayed, up to the first hole in the track/sector list.

The creative among you will want to add many bells and whistles to my little program.  Perhaps 80-column display, showing an entire sector at a time rather than half a sector.  Perhaps display of the bytes in both hex and ASCII on the same line.  Perhaps the ability to scan back and forth through a file, using the arrow keys.  All these are possible, and not too difficult.  Have fun!
