GetDriveTypeA with Mac osX ?

I'm a little bit confused with my mac mini os :) this is the code that i
use under pc for know if a drive is connected. Is there a function
to do the same think under mac os ? sorry for this noob question
but it's my first mac ...

' ------------------------------
' Test drive connection and type
' ------------------------------
Function IGL_GetDriveList(Parent:IGL_Combo)
Local DriveType:Int
Local DriveIcon:String

For Local Read=65 To 90
DriveType=IGL_GetDriveExist(Chr(Read)+":/")

If DriveType>1 Then
If DriveType=2 Then DriveIcon=IGL_Icon_FLOPPY
If DriveType=3 Then DriveIcon=IGL_Icon_DRIVE
If DriveType=4 Then DriveIcon=IGL_Icon_NETWORK
If DriveType=5 Then DriveIcon=IGL_Icon_CDROM
If DriveType=6 Then DriveIcon=IGL_Icon_RAMDRIVE

Parent.CreateITem(Chr(Read)+":/",DriveIcon)
EndIf
Next
End Function

The function IGL_GetDriveExist is :

Extern "Win32"
Function IGL_GetDriveExist(DrivePath$z) = "GetDriveTypeA@4"
End Extern