Date   : Tue, 24 Jan 1984 15:06:00 EST (Tue)
From   : Mike Ciaraldi <ciaraldi@Rochester.ARPA>
Subject: Re: writing w/o opening

Under MP/M, there is a checksum in the FCB.
This gets set when you open the file, and you cannot
read or write on the file unless this checksum is correct.
So, the problem of wiping out your directory by not
opening the file first should not occur.

I don't know if this technique is used in newer products
such as CP/M-86 or CP/M-Plus

Mike Ciaraldi
ciaraldi@rochester