Category: DOS kernel
INT 21 - MS-DOS 7.0+ - GENERIC IOCTL - UNLOCK LOGICAL VOLUME AX = 440Dh CX = 086Ah / 486Ah (category code 08h for FAT12/16, 48h for FAT32; minor code 6Ah) BL = drive number (00h=default,01h=A:,etc) Return: CF set on error AX = error code (01h,02h,etc.) (see #01680 at AH=59h/BX=0000h) CF clear if successful Note: the logical volume must be locked before direct disk accesses via INT 13 are permitted by Windows95 BUG: Windows98 will return an error (invalid function) if the specified drive number is zero or more than 32, but only allocated 26 bytes for recording locks, so BL=1Bh..20h will trash internal data structures SeeAlso: AX=440Dh"DOS 3.2+",AX=440Dh/CX=084Ah,AX=440Dh/CX=086Bh