Function 2Eh (46)        Set or Reset VERIFY Switch

    Turns the disk verify operation on or off.

       On entry:      AH         2Eh
                      AL         00h       to turn VERIFY off
                                 01h       to turn VERIFY on
                      DL         00h

       Returns:       Nothing

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    Function 2Eh turns the DOS VERIFY switch on or off. If VERIFY is on,
    DOS reads the CRC (cyclic redundancy check) bytes of the just-written
    data, and verifies that they are correct. Note that setting the VERIFY
    switch ON does NOT cause a read-after-write verification of data
    copied to the disk, only a verification of the CRC bytes.

       Notes:         In DOS 1 and 2 only, DL must be set to 0 before this
                      function is called.

                      Network disks do not support the verification
                      function.

                      Use Function 54h (Get Verify Setting) to determine
                      the current state of the VERIFY switch.