HOW TO: Multiple CD-ROM support with MCI

[Michael Sieber]

Hello!

I need to support multiple CD-ROM drives in my application (definitly more than one!).
And have have to implement it with the MCI API.
My problem is that I cannot specify a certain device, e.g. a drive number or something like
that and the MCI_OPEN command takes the first drive it finds as the CD-ROM drive.

How can I open specific CD-ROM drives?
And keep more than one MCI device with MCI_DEVTYPE_CDAUDIO open?

Thanx for all hints and solutions!

Michael Sieber
Erlangen, Germany

[Rauli Ikonen]

I wonder why would you want to support more than one CD-ROM drives, because (most likely) only one of them has connection to the sound card (the one MCI_OPEN selects, I suppose) and playing music with other CD-ROMs is therefore rather futile!

[Todd Jeffreys]

Here is some code I have that will open an MCI CD audio device on a certain drive. Call it like SetDriveLetter("e:\\");

void CDMCIPlayer::SetDriveLetter(LPCTSTR drive)
{
//cDriveLetter is a global or whatever that stores the current drive letter assigned
if (cDriveLetter == *drive) return;
MCI_OPEN_PARMS mciOpen;
TCHAR szElementName[4];
TCHAR szAliasName[32];
DWORD dwFlags;
DWORD dwAliasCount = GetTickCount();
DWORD dwRet;
TCHAR chDrive;

chDrive = *drive;

ZeroMemory( &mciOpen, sizeof(mciOpen) );

if (dDeviceID)
{
mciSendCommand(dDeviceID,MCI_STOP,MCI_WAIT,0);
mciSendCommand(dDeviceID,MCI_CLOSE,MCI_WAIT,0);
}

mciOpen.lpstrDeviceType = (LPTSTR)MCI_DEVTYPE_CD_AUDIO;
wsprintf( szElementName, TEXT("%c:"), chDrive );
wsprintf( szAliasName, TEXT("CD%lu:"), dwAliasCount );

mciOpen.lpstrElementName = szElementName;
mciOpen.lpstrAlias = szAliasName;

dwFlags = MCI_OPEN_ELEMENT | MCI_OPEN_SHAREABLE | MCI_OPEN_ALIAS |
MCI_OPEN_TYPE | MCI_OPEN_TYPE_ID | MCI_WAIT;

dwRet = mciSendCommand(0, MCI_OPEN, dwFlags, (DWORD)(LPVOID)&mciOpen);

if ( dwRet != MMSYSERR_NOERROR ) return;

cDriveLetter=chDrive;
dDeviceID=mciOpen.wDeviceID;
}