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====== Int 21H, AH=36H ======

===== Version =====

2 and higher

===== Brief =====

GET FREE DISK SPACE

===== Family API =====

[[en:docs:fapi:dosqfsinfo|DosQFSInfo]]

===== Input =====

        AH = 36h
        DL = drive number (00h = default, 01h = A:, etc)

===== Return =====

 AX = FFFFh if invalid drive
        else
            AX = sectors per cluster
            BX = number of free clusters
            CX = bytes per sector
            DX = total clusters on drive

===== Notes =====

  free space on drive in bytes is AX * BX * CX
        total space on drive in bytes is AX * CX * DX
        "lost clusters" are considered to be in use
        according to Dave Williams' MS-DOS reference, the value in DX is
          incorrect for non-default drives after ASSIGN is run
        this function does not return proper results on CD-ROMs;
          use AX=4402h"CD-ROM" instead
        (FAT32 drive) the reported total and free space are limited to 2G-32K
          should they exceed that value
          
===== See also =====

 AH=1Bh,AH=1Ch,AX=4402h"CD-ROM",AX=7303h

===== Note =====

Text based on [[http://www.cs.cmu.edu/~ralf/files.html|Ralf Brown Interrupt List Release 61]]

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