Contributor: PETER LOUWEN
{
BP> Is there some way I can use interrupts or whatever to detect whether
BP> the "file name" contained in the S string variable is a device name
BP> (such as "CON", "LPT1", "AUX", etc) or not?
Yes: use the ubiquitious INT 21ドル. }
FUNCTION IsDevice(CONST Fname: PathStr): boolean;
{ -- Returns TRUE if named file is actually a device.
-- Example: IsDevice('CON') = TRUE, IsDevice(paramstr(0)) = FALSE.
-- N.B.: returns FALSE if FName is a non-existent file. }
VAR Regs: Registers;
F : FILE;
FH : word ABSOLUTE F;
BEGIN IsDevice := FALSE;
assign(F, Fname);
reset(F, 1);
IF IOresult 0 THEN exit;
WITH Regs
DO BEGIN { -- Get information about file: }
AX := 4400ドル;
BX := FH;
MsDos(Regs);
IF NOT odd(Flags) AND (DL AND 80ドル 0)
THEN IsDevice := TRUE
END;
close(F);
IF IOresult 0 THEN ;
END;