Compatibility: 1.0+
Expects: AH    2eH
AL    0 to turn verify OFF
1 to turn verify ON
DL    0 (need for DOS 1.x and 2.x only)
                                                                  
Returns: none
                                                                  
Info: Selects whether DOS should verify (check the CRC  on) each sector
after it is written to disk.

This slows down disk write operations, but it ensures maximum
data integrity.

DOS Fn 54H returns the current DOS verify status.

Notes:   The Verify flag is a system-global setting.  If you change it,
you should restore the original value before exiting.

See Also: Fn 54H (get verify
- -

DOS Fn 2eH: Set/Reset Verify Switch