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<TITLE>Int 21/AH=49h
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Int 21/AH=49h - DOS 2+ - FREE MEMORY -
AH = 49h
ES = segment of block to free
Return: CF clear if successful
CF set on error
AX = error code (07h,09h) (see #01680 at AH=59h/BX=0000h)
Notes: apparently never returns an error 07h, despite official docs; DOS 2.1+
code contains only an error 09h exit
DOS 2.1-6.0 does not coalesce adjacent free blocks when a block is
freed, only when a block is allocated or resized
the code for this function is identical in DOS 2.1-6.0 except for
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<h2>Int 21/AH=49h
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<h3><font color=#C00040>DOS 2+ - FREE MEMORY</font></h3>
<PRE>
AH = 49h
ES = segment of block to free<br>
<p><b>Return:</b><br>CF clear if successful
CF set on error
AX = error code (07h,09h) <a href="javascript:if(confirm('http://www.ctyme.com/intr/rb-0000.htm \n\nThis file was not retrieved by Teleport Pro, because it was unavailable, or its retrieval was aborted, or the project was stopped too soon. \n\nDo you want to open it from the server?'))window.location='http://www.ctyme.com/intr/rb-0000.htm#Table0'" tppabs="http://www.ctyme.com/intr/rb-0000.htm#Table0"></a>(see #01680 at AH=59h/BX=0000h)
</PRE>
<p><b>Notes:</b>
Apparently never returns an error 07h, despite official docs; DOS 2.1+
code contains only an error 09h exit.
DOS 2.1-6.0 does not coalesce adjacent free blocks when a block is
freed, only when a block is allocated or resized.
The code for this function is identical in DOS 2.1-6.0 except for
calls to start/end a critical section in DOS 3.0+
<p><b>See Also:</b>
<a href="rb-2934.htm" tppabs="http://www.ctyme.com/intr/rb-2934.htm">AH=48h</a> - <a href="rb-2936.htm" tppabs="http://www.ctyme.com/intr/rb-2936.htm">AH=4Ah</a>
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DOS Kernel</a>
- <a href="int-21.htm" tppabs="http://www.ctyme.com/intr/int-21.htm">
Int 21h</a>
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