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KILLIT.C

 /* 
 *KILLIT.COM - A small utility to kill or re-enable the PrtScr function 
 *      Usage: Call with no argument to disable PrtScr function
               Call with any argument to enable PrtScr function
                  Written by M.L.  Lesser, 10/27/89
        Compiled with Turbo C (TCC) v 2.00, switches -mt -lt -o
                to link as COM file
 */

 #include <MIO><N>.h

 char far *PrtScr = (void far *)((unsigned long)0x50 << 16);

 void main(argc)
    {
    if (argc == 1)      /* No arguments on the command line */
       {
       *PrtScr = 1;   /* Set PrtScr "busy" signal */
       cprintf("Print screen function has been disabled");
       }
    else
       {
       *PrtScr = 0;   /* Set PrtScr <169>available<170> signal */
       cprintf("Print screen function has been enabled");
       }
    }

