sf_dde_exist          DDE provide memory area which is never cleared
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    function logical sf_dde_exist prototype

    function char( 8 ) sf_dde_time prototype

    function char( 85 ) sf_dde_message prototype

    procedure sf_dde_send_message prototype
      parameters const char( 85 ) dde_message

    The DDE functions provide a memory area which is never cleared, only
    overwritten.  This allows a Child executable to pass a message
    to the Parent executable.

    Example:

    sf_dde_send_message( "You can't see me..." )

    if sf_dde_exist()
      ? sf_dde_time()
      ? sf_dde_message()   && but now you can...
    endif