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─────PWB Extensions─────────────────────────────────────────────────────────
 
     All extension functions must have the prototype:
 
     PWBFUNC funcname( unsigned argData, ARG far *pArg, flagType fMeta );
 
     The return type macro contains all the type modifiers required for
     extension functions. The macro evaluates to the following
     attributes:
 
          flagType _pascal _loadds far
 
     The flagType return value of extension functions is a Boolean
     value. It can be tested by any PWB macro that calls your function,
     so it is good practice to return a meaningful value. You should
     return TRUE for success and FALSE for failure.
 
     You must define the following arguments even if your function does
     not use them (you can use different names):
 
     Argument     Description
 
     argData       Keystroke used to invoke the function. Should be
                   ignored in extension functions.
 
     pArg          Pointer to a structure that contains variable
                   information about the arguments passed by the user.
 
     fMeta         Flag for whether Meta was set by a previous Meta
                   command. TRUE if Meta is set, FALSE if Meta is
                   not set.
 
     See: ◄Extension Function Arguments►
          ◄Extension Argument Structure►
 
     TIP: If you do not use all arguments and you compile with a high
          warning level, the compiler produces a warning about unused
          formal arguments. Use the following pragma to suppress this
          warning.
 
               #pragma warning( disable:4100 )  //Allow unused arguments
                                    -♦-