| Function | Description |
| 0 | Duplicate handle (params and result same as in INT 21H AH=45H) |
| 1 | Terminate MVM with error message (top of stack - far pointer to message ASCIIZ) |
| 2 | Terminate MVM and return code to parent process from AX |
| 3 | Close file handle (interface not investigated yet) |
| 4 | Reset disk buffers |
| 5 | Get current PSP (interface not investigated yet) |
| 6 | Select default drive (params and result same as in INT 21H AH=0EH) |
| 7 | Set DTA from DS:DX (params and result same as in INT 21H AH=1AH) |
| 8 | Get version (interface not investigated yet) |
| 9 | Write file handle (interface not investigated yet) |
| 10 | Set system date (params and result same as in INT 21H AH=2BH) |
| 11 | Set system time (params and result same as in INT 21H AH=2DH) |
| 12 | Get system date (result same as in INT 21H AH=2AH) |
| 13 | Get system time (result same as in INT 21H AH=2CH) |
| 14 | Read file handle (interface not investigated yet) |
| 15 | Set file handle position (interface not investigated yet) |
| 16 | Delete directory (params and result same as in INT 21H AH=3AH) |
| 17 | Create directory (interface not investigated yet) |
| 18 | Get current directory (params and result same as in INT 21H AH=47H) |
| 19 | Change directory (params and result same as in INT 21H AH=3BH) |
| 20 | Get/Set file time (interface not investigated yet) |
| 21 | Commit file (interface not investigated yet) |
| 22 | Find first file using FCB (interface not investigated yet) |
| 23 | Find next file using FCB (interface not investigated yet) |
| 24 | |
| 25 | Find first file (interface not investigated yet) |
| 26 | |
| 27 | |
| 28 | Open file (interface not investigated yet) |
| 29 | Delete file using FCB DS:DX → unopened FCB ES → environment segment |
| 30 | Rename file using FCB (params and result same as in INT 21H AH=17H) |
| 31 | Delete file (interface not investigated yet) |
| 32 | Rename file (interface not investigated yet) |
| 33 | |
| 34 | |
| 35 | |
| 36 | |
| 37 | Open file using FCB (interface not investigated yet) |
| 38 | |
| 39 | Close file using FCB (interface not investigated yet) |
| 40 | |
| 41 | |
| 42 | |
| 43 | |
| 44 | Set VERIFY flag from AL |
| 45 | Find next file (interface not investigated yet) |
| 46 | Create new file (interface not investigated yet) |
| 47 | Create temp file (interface not investigated yet) |
| 48 | |
| 49 | Parse filename to FCB (params and result same as in INT 21H AH=29H) |
| 50 | |
| 51 | |
| 52 | |
| 53 | |
| 54 | |
| 55 | |
| 56 | |
| 57 | |
| 58 | |
| 59 | |
| 60 | |
| 61 | Absolute disk read (interface not investigated yet) |
| 62 | Absolute disk write (interface not investigated yet) |
| 63 | |
| 64 | |
| 65 | |
| 66 | |
| 67 | |
| 68 | |
| 69 | |
| 70 | |
| 71 | |
| 72 | |
| 73 | |
| 74 | |
| 75 | |
| 76 | |
| 77 | |
| 78 | |
| 79 | |
| 80 | |
| 81 | |
| 82 | |
| 83 | |
| 84 | |
| 85 | |