INT D4 - PC-MOS/386 v5.01 - WRITE CONTROL BLOCK DATA INTO SCB OR TCB            
	AH = 29h
	BX = offset into control block at which to start writing
	CX = number of bytes to write
	DX = segment/selector of control block obtained via AH=26h or AH=27h
	DS:SI -> buffer containing data to be written
Return: CF clear if successful
	CF set on errro
	    AX = error code (see also #01680 at INT 21/AH=59h/BX=0000h)
		05h access denied due to an invalid segment/selector
Note:	 this function performs no bounds checking
Program: PC-MOS/386 is a multitasking/multiuser MS-DOS-compatible operating
	  system by The Software Link, Inc.
SeeAlso: AH=26h,AH=27h,AH=28h,AH=2Ah