Pointers to structures & functions arguments

This is a discussion on Pointers to structures & functions arguments within the C Programming forums, part of the General Programming Boards category; I'm calling my function like this Code: GdkColor *color; // structure showColor(&color); And my function is written like this Code: ...

  1. #1
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    Pointers to structures & functions arguments

    I'm calling my function like this
    Code:
    GdkColor *color; // structure
    showColor(&color);
    And my function is written like this
    Code:
    void showColor(GdkColor *color) {
    	GdkWindow *rootwin;
     	GdkImage *image;
    	GdkColormap *cmap;
    	gint x, y;
    	guint32 pixel;
    	GdkDisplay *display = NULL;
    	GdkScreen *screen = NULL; 
    	display = gdk_display_get_default ();
    	screen = gdk_display_get_default_screen (display); 
    	gdk_display_get_pointer (display, NULL, &x, &y, NULL);
    	rootwin = gdk_screen_get_root_window(gdk_screen_get_default());
    	cmap = gdk_screen_get_system_colormap(gdk_screen_get_default());
    
    	image = gdk_drawable_get_image(rootwin, x, y, 1, 1);
    	pixel = gdk_image_get_pixel(image, 0, 0);
    	g_object_unref(image);
    
    	gdk_colormap_query_color(cmap, pixel, &color);
    	color->red = color->red / 65535.0;
    	color->green = color->green / 65535.0;
    	color->blue = color->blue / 65535.0;
    }
    I'm getting errors on the color pointer to the structure..

  2. #2
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    color is a pointer, showColor takes a pointer, showColor(color); is sufficient (no &)

  3. #3
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    I'm also getting errors when calling the color elements..

  4. #4
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    I'm sure we've mentioned before, but "Post your actual error messages!!!"
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    Sorry, I've mistaken

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