INT 21 - DOS 1+ - READ RANDOM RECORD FROM FCB FILE
AH = 21h
DS:DX -> opened FCB (see AH=0Fh)
Return: AL = status
00h successful
01h end of file, no data read
02h segment wrap in DTA, no data read
03h end of file, partial record read
[DTA] = record read from file
Notes:  the record is read from the current file position as specified by the
random record and record size fields of the FCB
the file position is not updated after reading the record
if a partial record is read, it is zero-padded to the full size
not supported by MS Windows 3.0 DOSX.EXE DOS extender
SeeAlso: AH=22h,AH=27h,AH=3Fh

See also: 2114

2121 - DOS 1+ - READ RANDOM RECORD FROM FCB FILE