Programmer 7500/MAX_PROGRAMMERS.iso/INFO/TURBOPAS/TPASBOOK.ZIP/KEYSTAT.C86

Text File | 1985-06-08 | 466 b | 16 lines

FUNCTION KEYSTAT(VAR CH : CHAR) : BOOLEAN;

TYPE REG_PACK = RECORD
                  AX,BX,CX,DX,BP,SI,DI,DS,ES,FLAGS : INTEGER
                END;

VAR REGISTERS : REG_PACK;

BEGIN
  REGISTERS.AX := $0600;   { DOS call 6: Direct Console I/O }
  REGISTERS.DX := 255;     { Selects non-echo read function }
  BDOS(REGISTERS);         { Make the DOS call }
  CH := CHR(REGISTERS.AX); { The character is returned in AX }
  KEYSTAT := CH <> CHR(0)
END;