Following are the MS-DOS drive-management functions:
| Function | Description | Version |
| 0Dh | Reset Drive | 1.0 |
| 0Eh | Set Default Drive | 1.0 |
| 19h | Get Default Drive | 1.0 |
| 1Ah | Set Disk Transfer Address | 1.0 |
| 1Bh | Get Default Drive Data | 2.0 |
| 1Ch | Get Drive Data | 2.0 |
| 1Fh | Get Default DPB | 5.0 |
| 2Fh | Get Disk Transfer Address | 2.0 |
| 32h | Get DPB | 5.0 |
| 3305h | Get Startup Drive | 2.0 |
| 36h | Get Disk Free Space | 2.0 |