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====== Int 21H, AH=52H ======

===== Version =====

2 and higher

===== Brief =====

"SYSVARS" - GET LIST OF LISTS

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


===== Input =====

	AH = 52h

===== Return =====

   ES:BX -> DOS list of lists (see #01627)

===== Notes =====

	partially supported by OS/2 v1.1 compatibility box (however, most
	  pointers are FFFFh:FFFFh, LASTDRIVE is FFh, and the NUL header "next"
	  pointer is FFFFh:FFFFh).
	partially supported by the Windows NT DOS box; contains only a
	  rudimentary Current Directory Structure (see #01645)
	on return, ES points at the DOS data segment (see also INT 2F/AX=1203h)
	Quarterdeck's suggested check for the use of its DOSDATA.SYS or
	  DOS-UP.SYS is to test whether the list-of-lists segment is greater
	  than the segment of the first memory block; a better check for
	  DOS-UP.SYS is INT 21/AX=2B01h/CX=444Dh
	because not all DOS workalikes support all fields in the List of Lists,
	  applications should ensure that pointers are neither 0000h:0000h
	  nor FFFFh:FFFFh before using them
	Windows for Workgroups 3.11 network and Windows95 set the path to
	  the local drive and directory even for network drives; in that
	  case the UNC form \\SERVER\SHARE can be obtained with
	  INT 21/AX=5F02h or INT 21/AX=5F46h. LapLink RemoteAccess does the
	  same even for INT 21/AX=5F02h
	Windows95 GUI no longer returns the true path for a SUBSTed drive,
	  but MS-DOS 7.00 does; use INT 21/AH=60h to obtain the true name
          
===== See also =====

 INT 2F/AX=1203h

===== Note =====

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

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