Category: <b>DOS-based task switchers/multitaskers</b>
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<pre><b>INT 21 - Software Carousel - SET TASK SWITCH CALLBACK</b>

	AX = DF0Bh
	BH = interrupt number or 00h
	BL = function number to invoke on partition switch
	CL = function number to call when it is safe for resident programs
		to perform DOS calls
	DS:DX -&gt; FAR function to call if BH=00h
Return: AL = status
	    00h Carousel not running
	    01h successful
	    FFh unsucessful
		AH = error code (01h,03h) (see <a href=../../it/13/18.html>#01813</a>)
Notes:	the specified interrupt or FAR function is called with AH set to the
	  appropriate one of the values specified in BL and CL, and BL set to
	  the new task number
	the function specified by CL will not be called until the notification
	  is enabled with AX=DF0Ch
SeeAlso: AX=DF0Ch
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