🚀 go-pugleaf

> Is there any way of disabling DOS internal commands ?  Alternatively
> can DOS be persuaded to execute a program of the same name as a DOS
> internal command without explicitly specifying a path ?

The easiest way to disable internal commands is to alter a second
copy of COMMAND.COM with something like Norton.  Search for the
text of the command you wish to alter.  Notice that the commands
are listed on all uppercase.  Simply changing the command to lowercase
will disable it.

This method works because DOS converts you command line to uppercase
before proccessing it.  It then performs a case-sensitive compare
with all of the internal commands.  Since "COPY" won't match "copy" the
command is effectively disabled.  In addition changing the command
to lower case will allow you to easily find where the change was
made in case you wish to alter it later.

If you rename VCOPY to COPY users will really be executing a virus
free copy.  Remember, never try to patch your only copy of 
COMMAND.COM.  Always attempt patches on a backup copy.

Robert F. Nee <nee@cf_su20.sbi.com>