INT 21 - DOS 1+ - WRITE RANDOM RECORD TO FCBsee File Control Block FILE
	AH = 22h
	DS:DX -> opened FCBsee File Control Block (see #01345)
	Disk Transfer Area contains record to be written
Return: AL = status
	    00h successful
	    01h disk full
	    02h segment wrap in DTAsee Disk Transfer Address
Notes:	the record is written to the current file position as specified by the
	  random record and record size fields of the FCBsee File Control Block
	the file position is not updated after writing the record
	if the record is located beyond the end of the file, the file is
	  extended but the intervening data remains uninitialized
	if the record only partially fills a disk sector, it is copied to a
	  DOS disk buffer to be written out to disk at a later time
	not supported by MS Windows 3.0 DOSX.EXE DOS extender
SeeAlso: AH=15h,AH=21h,AH=28h,AH=40h