Category: <b>DESQview/TopView and Quarterdeck programs</b>
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<pre><b>INT 15 - TopView - SEND MESSAGE - "SUBFROM" - SEND MAILBOX MESSAGE/STAT BY REF</b>

	AH = 12h
	BH = 0Bh
	BL = mailbox to write to
	    00h handle is DWORD on top of stack
	    02h default mailbox of task whose handle is on top of stack
	    03h current task's default mailbox
	STACK:	DWORD	status (low byte)
		DWORD	length of message
		DWORD	address of message
Return: STACK popped
Notes:	only a pointer to the message is stored, but the write may still fail
	  due to insufficient memory
	under DV 2.2+, failed mailbox writes may return CF set (see AX=DE15h)
SeeAlso: AH=12h/BH=0Ah"MAILBOX"
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