Inaccessible CP/M programs in Altair32

From: Allison <ajp166_at_bellatlantic.net>
Date: Mon Nov 26 09:11:11 2001

CP/M marks a file delete by changing the first byte of the directory
record with E5h to replace a value of 00 to less than 040h. It also
does so for every file extent for that file in the directory.

A completely empty directory by default contained the E5h mark
as formatters back tehn used that as the data fill on a freshly
formatted disk.

Allison

-----Original Message-----
From: John Foust <jfoust_at_threedee.com>
To: classiccmp_at_classiccmp.org <classiccmp_at_classiccmp.org>
Date: Monday, November 26, 2001 9:30 AM
Subject: Re: Inaccessible CP/M programs in Altair32


>
>When CP/M deleted a file, did it just put a zero
>at the start of the filename (like DOS), or did it erase the
>entire field? Perhaps Rich saw deleted files...
>
>- John
>
>
Received on Mon Nov 26 2001 - 09:11:11 GMT