INT 15 - DESQview v2.20+ - SEND MESSAGE - "SETFLAGS" - SET OBJECT FLAGS
	AH = 12h
	BH = 15h
	BL = object
	    00h DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address. on top of stack
		mailbox, keyboard, or pointer only
	    02h mailbox for task whose handle is on top of stack
	    03h mailbox for current task
	    04h keyboard for task whose handle is on top of stack
	    05h keyboard for current task
	STACK: DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address. flags (see #00453,#00454)
Return: STACK popped
Notes:	only available if the API(Application Program[ming] Interface) The defined set of calls which a program may make to interact with or request services of the operating system or environment under which it is running.  Because the inputs and outputs of the calls are well-defined, a program using the API can continue using the identical calls even if the internal organization of the program providing the API changes. level has been set to at least 2.20
	equivalent to performing SUBFROM and ADDTO calls on the object
	if a mailbox has bits 4 or 5 set, you must use "READINTO" rather than
	  "READ" (see AH=12h/BH=13h"READINTO") to retrieve messages
SeeAlso: AH=12h/BH=0Ah,AH=12h/BH=0Bh,AH=12h/BH=16h


Bitfields for DESQview mailbox object flags:
Bit(s)	Description	(Table 00453)
 0	all mail messages in common memory
 1	allow write even if closed
 2	don't erase messages when mailbox closed
 4	(DV/X) append messages with like status and sender (stream-oriented
	  mail)
 5	(DV/X) store mail in expanded memory (pool grows as needed)
 6	(DV/X) make mailbox into non-owned mailbox


Bitfields for DESQview keyboard object flags:
Bit(s)	Description	(Table 00454)
 5	exclusive input when keyboard in use for input