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		       -  Clarion Technical Support  -

	 This program shows one way to use the EXTERNAL statement.
    In this example the EXTERNAL statement is used to pass a key
    name to a table procedure.	Passing structures and fields
    externally allows you to create "generic" procedures or functions.
    This example has a generic TABLE procedure that display records
    from a file depending on the KEY that is passed to it from the
    MENU procedure.  Both the TABLE and the MENU have been converted
    to "OTHER" procedures since Designer does not support external
    parameters on menu items.


    4 Important Notes:

    1) In Designer, you will not be able to use external parameters
    on menu items.  Designer is not setup to handle external parameters
    on menu items. However, anywhere Designer gives you the ability
    to enter your own code you can use external parameters on your
    procedure calls.

    2) A good example of how to pass a file name as an external parameter
    is in the 218A model files.	 Since the code used to open or share
    a file is exactly the same except for the file name, as of release
    2108,  the G_OPENFILES() procedure passes the file name (externally)
    to the G_OPENFILES2() procedure.  This G_OPENFILES2() procedure
    contains all the code necessary to open a file.  This eliminates
    the need for redundant code.

    3) When passing structures you must also pass any items in that
    structure that you plan on referencing in the called procedure.
    EX.	 If you pass a key name as an external parameter the fields
    in that key CANNOT be referenced unless they are passed also.

    4) Structures passed externally require a KEYWORD attribute to
    identify them. ie,

	  FILEA	    EXTERNAL,FILE
	  KEYX	    EXTERNAL,KEY
	  SCREENG   EXTERNAL,SCREEN
	  ARRAYV    EXTERNAL,DIM(1,1)	  !Pg. 3-25 Lang Ref Man.
	  DOSFILE   EXTERNAL,DOS
	  REPORTH   EXTERNAL,REPORT
	  TABLEQ    EXTERNAL,TABLE

       Fields and variables only require the EXTERNAL attribute.
       ie,
	  field1    EXTERNAL
	  field2    EXTERNAL
	  var1	    EXTERNAL
	  pointer   EXTERNAL
	  counter   EXTERNAL