Example 1

 This program demonstrates how to receive parameters passed from a
 Clipper application, from within C, using the Clipper Extend system.


 /***
 *   Test.prg
 *
 *   By: Scott McIntosh, Nantucket Corp.
 *
 *   Program to test the TestC.c program.
 *
 *   Compile: CLIPPER test /n /a /w
 *
 *      Link: RTLINK FI test, testc LIB clipper, llibca /NOE
 */

 PROCEDURE Main()

    // define a set of misc. data to check the C function with.
    // The array in aVar1 contains a nested array. The nested array
    // can not be accessed through the extend system!
    //
    LOCAL aVar1 := { "Hello, world", 12, DATE(), .F., { "One", "Two" } }
    LOCAL nVar1 := 1234
    LOCAL cVar1 := "This string is bigger than 30 characters!"
    LOCAL dVar1 := DATE()
    LOCAL lVar1 := .T.
    LOCAL xVar

    // and create a new set of data to pass by reference
    //
    LOCAL aVar2 := { "First Element", "Second Element", "Third Element" }
    LOCAL nVar2 := -1234
    LOCAL cVar2 := "A shorter string"
    LOCAL dVar2 := CTOD( "9/15/91" )
    LOCAL lVar2 := .F.

    CLS

    ExtendTest( aVar1,  nVar1,  cVar1,  dVar1,  lVar1, xVar,   ;
                @aVar2, @nVar2, @cVar2, @dVar2, @lVar2, )

    SETPOS( MAXROW(), 0 )

 QUIT


 /***
 *   TestC.c
 *
 *   By: Scott McIntosh, Nantucket Corp.
 *
 *   Demonstrates how to use the Clipper extend system to receive parameters
 *   from Clipper.  This program simply displays the types and values of the
 *   parameters that are passed to it.
 *
 *   Display is written to stdout and is DOS re-directable.
 *
 *   Compile: cl /AL /c /FPa /Gs /Oalt /Zl testc.c
 */

 #include "extend.h"

 CLIPPER ExtendTest( void )
 {
    int parNum;                     // current parameter number
    int arrIndex;                   // current array index number

      // process each parameter in turn
    for( parNum = 1; parNum <= PCOUNT; parNum++ )
    {
         // make sure the array index counter is zeroed
       arrIndex = 0;

         // display the current parameter number
       cprintf(  "\r\nParameter %2i    ", parNum );

         // show the type of the current parameter
       ShowType( _parinfo( parNum ), parNum, arrIndex );

       if( ISARRAY( parNum ) )
       {

            // parameter is an array - process each element in turn
          for( arrIndex = 1; arrIndex <= ALENGTH( parNum ); arrIndex++ )
          {
               // indent and display the current array element number
             cprintf(  "       Element %2i    ", arrIndex );

               // display the current array element type
             ShowType( _parinfa( parNum, arrIndex ), parNum, arrIndex );
          }
       }
    }

    _ret();

 }


 /***
 *   ShowType( int parameterType, int parameterNumber, int arrayElement )
 *
 *   Processes parameters and the individual elements of array parameters.
 *
 *   Displays the numeric value of the data type of the parameter/element,
 *   a text description of the type (i.e.: "Character" ), and the value of
 *   the parameter/element.
 *
 *   The text description will be preceded with a "@" to indicate a
 *   parameters that was passed by reference.
 *
 *   The following substitutions are made for the actual value of the
 *   parameter/element:
 *       Arrays     display  "{...}"
 *       Logicals   display  0 or 1  ( 0 = .F., 1 = .T. )
 *       Characters display  First 30 characters of the string
 *       Undefines  display  "???"
 */

 void ShowType( int type, int param, int index )
 {

      // show the correct text description and value for the current item
    switch ( type )
    {
       case UNDEF:
          cprintf( "Undefined    Value: ???\r\n" );
          break;

       case CHARACTER:
          cprintf( "Character    Value: %.30s\r\n", _parc( param, index ) );
          break;

       case NUMERIC:
          cprintf( "Numeric      Value: %i\r\n", _parnl( param, index ) );
          break;

       case LOGICAL:
          cprintf( "Logical      Value: %i\r\n", _parl( param, index ) );
          break;

       case DATE:
          cprintf( "Date         Value: %s\r\n", _pards( param, index ) );
          break;

       case ARRAY:
          cprintf( "Array        Value: {...}\r\n" );
          break;

       case (MPTR + UNDEF):
          cprintf( "@Undefined   Value: ???\r\n" );
          break;

       case (MPTR + CHARACTER):
          cprintf( "@Character   Value: %.30s\r\n", _parc( param, index ) );
          break;

       case (MPTR + NUMERIC):
          cprintf( "@Numeric     Value: %i\r\n", _parni( param, index ) );
          break;

       case (MPTR + LOGICAL):
          cprintf( "@Logical     Value: %i\r\n", _parl( param, index ) );
          break;

       case (MPTR + DATE):
          cprintf( "@Date        Value: %s\r\n", _pards( param, index ) );
          break;

       case (MPTR + ARRAY):
          cprintf( "@Array       Value: {...}\r\n" );
          break;
    }

    return;

 }


 /* EOF: Example 1 */