INT 21 - DOS 3.0+ - IOCTL - CHECK IF BLOCK DEVICE REMOVABLE
AX = 4408h
BL = drive number (00h = default, 01h = A:, etc)
Return: CF clear if successful
AX = 0000h if removable
= 0001h if fixed
CF set on error
AX = error code (01h,0Fh) (see AH=59h)
SeeAlso: AX=4409h,INT 2F/AX=122Bh

See also: 214400

214408 - DOS 3.0+ - IOCTL - CHECK IF BLOCK DEVICE REMOVABLE