*****************************************************************
* Neveprise Inc. Delphi FAQ					*
*****************************************************************
* Section: Files		Topic:   Disk presence		*
* Created: July 27th, 1999	Revised: July 27th, 1999 	*
* Updates: www.neveprise.de	Info:	 support@neveprise.de	*
*****************************************************************

Q: How can I check if a disk is inserted in a drive?

A: To do it, we just have to perform an I/O operation on the target
	drive, e.g. changing the directory. Normally this would
	cause an error, and that is what we need: if an error occurs,
	we know that the drive is not ready (cos we change to the
	root dir, otherwise it could mean that the directory does not
	exist). The only problem is that an error also causes a dialog
	box informing the user, so we have to supress it:


function IsDriveReadyH(Drive: char): boolean;
var  OldErrorMode : Word;
     OldDirectory : string;
begin
//remind old error mode and tell windows not to display errors
OldErrorMode := SetErrorMode(SEM_NoOpenFileErrorBox);
GetDir(0, OldDirectory); //remind old / actual path and drive
{$I-} //just to go sure (compiler directive: no error msg)
ChDir(Drive+':\'); //go to root of drive to check
{$I+}
if IoResult<>0 then Result:=false else Result:=true;
//above: =0 means, no input/output action error occured
ChDir(OldDirectory); //go back to our previous location
SetErrorMode(OldErrorMode); //and set original error mode
end;



	Blazko