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====== Int 21H, AH=49H ======

===== Version =====

2 and higher

===== Brief =====

FREE MEMORY

===== Family API =====


===== Input =====

	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
	  calls to start/end a critical section in DOS 3.0+
          
===== See also =====

 AH=48h,AH=4Ah

===== Note =====

Text based on [[http://www.cs.cmu.edu/~ralf/files.html|Ralf Brown Interrupt List Release 61]]

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