Category : Files from Magazines
Archive   : VOL9N15.ZIP
Filename : CONCEAL.DOC

CONCEAL


Michael J. Mefford September 26, 1990 (Utilities)

Purpose: Provides file security through password protection of
selected files and a screen-blanking system activated either by a hotkey or
by a period of keyboard inactivity. Most options explained below have ON and
OFF states (default on) that may be entered with the parameters.

Format: CONCEAL [/P password] [filespec] [options]

Remarks: CONCEAL.COM is normally loaded as a TSR requiring
approximately 1K of RAM, via the AUTOEXEC.BAT line

CONCEAL /S

Files are then protected with the command

CONCEAL filespec /S

This applies the DOS System attribute to the filespec, making it
invisible to DOS. CONCEAL then monitors and fails any attempts to remove the
System attribute, and any DOS calls to open, delete, rename, or change the
file attribute of protected files unless the proper password is supplied.
Legitimate access is provided by the command

CONCEAL /P password filespec /S OFF


This turns off the filespec System attribute, which must later be
reapplied. (The /F option allows password-access without removing the System
attribute, but may not work with all applications.) The default password
SHAZAM can be changed with the /N parameter option. Other file attributes
(Archive, System, Hidden, Read-only) can be changed with the /A option:

CONCEAL /A filespec [+|-A] [+|-S] [+|-H] [+|-R]

Hardware screen blanking is provided by entering

CONCEAL /B nn

where nn is a number of minutes (0 - 60). The default is 3 minutes,
and a value of 0 for nn turns blanking off. The /G option may be entered
instead of /B to provide a bouncing ball instead of a blank screen display.
Instant blanking is achieved with a hotkey (default Alt-Z), which may be
changed to any Alt- or Ctrl- alphanumeric key with the /H option. From
graphics mode, the /G option defaults to /B. To blank over graphics
applications such as Windows, use the /O parameter. Adding the /T switch
will require password entry rather than a simple keystroke to terminate
screen blanking. The /U switch uninstalls CONCEAL.