Platform SDK: Win32 API

Int 21h Function 440Dh Minor Code 6Eh (FAT32)

Retrieves information about the swap file.

mov ax, 440Dh       ; generic IOCTL
mov ch, DeviceCat       ; see below
mov cl, 6Eh             ; Find Swap File  
mov dx, seg PathBuf     ; see below
mov ds, dx
mov dx, offset PathBuf
int 21h

jc  error_handler
mov [PagerType], ax            ; pager type
mov WORD PTR [FileSize], bx    ; swap file size in 4K pages
mov WORD PTR [FileSize+2], cx

Parameters

DeviceCat
Specifies a FAT16, FAT12 or FAT32 drive.
Value Description
08h FAT32, FAT16, or FAT12 drive.
48h FAT32, FAT16, or FAT12 drive. This value is supported on Windows 95 OEM Service Release 2 and later.

Note: Because this call may be implemented in the device driver, the 48h form of this call may fail on FAT16 or FAT12 media. Therefore, applications making the 48h form of this call must fall back on the 08h form if the 48h call fails.

PathBuf
Address of the buffer that receives the path of the swap file. To determine the maximum allowed length of a path for the volume, call Get Volume Information (Interrupt 21h Function 71A0h).

Return Values

Clears the carry flag, copies the swap file path to the given buffer, and sets the following registers if successful:

Value Description
AX Pager type. It can be 1 for no pager, 2 for paging through MS-DOS, and 3 for paging through the protected-mode input and output (I/O) supervisor.
CX:BX Current size of the swap file in 4K pages.

Otherwise, this function sets the carry flag and sets the AX register to an error value.