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====== Int 21H, AH=55H ======

===== Version =====

2 and higher

===== Brief =====

CREATE CHILD PSP

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


===== Input =====

	AH = 55h
	DX = segment at which to create new PSP
	SI = (DOS 3.0+) value to place in memory size field at DX:[0002h]

===== Return =====

   AL destroyed

===== Notes =====

	creates a "child" PSP rather than making an exact copy of the current
	  PSP; the new PSP's parent pointer is set to the current PSP and the
	  reference count for each inherited file is incremented
	(DOS 2.0+) sets current PSP to DX
	(DOS 3.0+) marks "no inherit" file handles as closed in child PSP
	this function is implemented using the same code as AH=26h, so unlike
	  other DOS 2+ functions, it does not return status in CF, instead
	  returning status in AL as DOS 1.x functions do (but it never puts an
	  explicit return value in AL)
          
===== See also =====

  AH=26h,AH=50h

===== Note =====

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

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