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 Additional Programs
------------------------------------------------------------------------------

 Security

     If CA-Clipper Tools functions that change interrupts are not properly
     uninstalled or if the Extended Driver is not implemented, you could use
     the INTSAVE.EXE and INTOFF.EXE programs as additional security.

     INTSAVE

     <Drive>:INTSAVE[/S|/R[<FileName>]]<RETURN>

     INTSAVE saves all 256 interrupt vectors to a file called INSAVE.TAB.
     Alternatively, a different filename can be selected, if multiple
     applications need to access the same path in a network.  A call with the
     /S switch saves the interrupt vectors,while a call with /R restores
     them.

     If the program is called without parameters, it explains its operation
     on the screen and, if required, displays a list of interrupt vectors
     that have been changed.

     INTOFF

     <Drive>:INTOFF <RETURN>

     This program represents an "emergency brake".  It sets the vectors
     described below to an IRET in the system ROM, so that there is no danger
     of a system crash as a result of erroneous interrupt vectors.  The mouse
     interrupt (033h) is also newly initialized and the timer tic rate is
     reset.  Memory resident programs are uncoupled from their interrupt
     vectors as well and are thereby rendered unusable. The program sets the
     following interrupt vectors to harmless IRETs:

     ------------------------------------------------------------------------
     Operation    Vector         Use in CA-Clipper Tools
     ------------------------------------------------------------------------
     IRET         Timer 1C       KEYSEC(), SHOWIME()
                  Alarm 4A       KEYTIME()
                  COM1 0C        V24 Functions
                  COM2 0B        V24 Functions
     INIT         Mouse 33       If foreign routines linked in
                  Timerspeed     SETTIC()
     ------------------------------------------------------------------------

     Both programs could be linked into a batch job which starts your
     CA-Clipper application. This would look as follows:

     ECHO OFF
     INTSAVE /S INTSAVE1.TAB

        CLIPPROG
     INTSAVE /R INTSAVE1.TAB
     ECHO ON

     With INTOFF, it would look like this:

     ECHO OFF
        CLIPPROG
        INTOFF
     ECHO ON

     This will avoid later system crashes.


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