typedefs and prototypes

[Griff Smith]

In article <7135 at bloom-beacon.MIT.EDU>, tada at athena.mit.edu (Michael Zehr) writes:
> 
> I'm writing a graphics interface library which ends up passing a lot
> of pointers to functions.  I've run into a problem with
> typedefs and prototypes:

> /* typedef and prototype declaration of a widget */
> 
> typedef void (*Keyboard_widget)(int key, void *data);
> 
> Keyboard_widget kb_widget1;
> 
> /* definition of a widget */
> 
> void kb_widget1(int c, void *data)
> {...}

> I get a "conflicts with previous declaration" at that point.  If I try
> to define the widget by the typedef, what syntax do i use???


/* Define the layout of a keyboard_widget function */

typedef void kb_widg_fn(int key, void *data);

/* Define a type that is a pointer to a keyboard_widget function */

typedef kb_widg_fn* Keyboard_widget;

/* I'm going to use kb_widget1, which is a keyboard_widget function */

kb_widg_fn kb_widget1;

/* And here it is */

void kb_widget1(int c, void *data) {}

/* This is accepted by C++, release 2.0; I can't speak for ANSI C */
-- 
Griff Smith	AT&T (Bell Laboratories), Murray Hill
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