Category: <b>disk I/O enhancements</b>
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<pre><b>INT 4B - Virtual DMA Specification - LOCK DMA REGION</b>

	AX = 8103h
	DX = flags (see <a href=../../it/20/32.html>#03220</a>)
	ES:DI -&gt; DMA descriptor structure (see <a href=../../it/21/32.html>#03221</a>,<a href=../../it/22/32.html>#03222</a>,<a href=../../it/23/32.html>#03223</a>)
Return: CF clear if successful
	    DDS physical address field filled in
	    DDS buffer ID field filled (0000h if no buffer allocated)
	CF set on error
	    AL = error code (see <a href=../../it/18/32.html>#03218</a>)
	    DDS region size field filled wth maximum contiguous length in bytes
BUGS:	Windows 3.0 does not correctly support automatic remapping or copying
	  in enhanced mode
	Windows 3.0 in enhanced mode does not return a correct code on error
SeeAlso: AX=8104h,AX=8105h

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