DOS Fn 27H: Read Random File Block

                                                         Compatibility: 1.0+ 
 Expects: AH    27H
          DS:DX address of an opened FCB
          CX    number of records to read
 Returns: AL    0 if read was successful and DTA is filled with data
                1 if EOF was reached and no data was read
                2 if DTA + FCB (RecSize * CX) would overrun a segment
                3 if EOF and a partial record was read (padded with 0s)
          CX    actual number of records read
    Info: Reads multiple records from the file starting at the file address
          specified by the randomRec field of the FCB.  Stores the data
          into memory starting at the DTA. Reads (FCB recSize*CX) bytes
          from the file.

          The randomRec and curBlk and curRec fields are adjusted to point
          to the next record (the first record that wasn't read).

See Also: Fn 3fH (read file via handle)
          FCB File I/O
          Handle-Oriented File I/O
          DOS Functions