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c - Using gcc, I am unable to get 3rd party library, Cairo, to link/compile

The errors that show up are for undefined symbols, not the Cairo functions I copied from the example, but what I guess are internal functions. I have looked around and tried using $(pkg-config --cflags --libs cairo), verbatim from a common online example using the terminal.

I tried that after using EXPORT=(my path to cairos .ps file).

I currently have one option in CodeBlocks 'Link Libraries' in the linker settings: /usr/lib/x86-linux-gnu/libcairo.a

Also, I have /usr/include/cairo in my compiler options.

Errors:

/usr/lib/x86_64-linux-gnu/libcairo.a(cairo-image-source.o)||In function _cairo_image_source_finish':| (.text+0x1c)||undefined reference topixman_image_unref'|

Plus 50 more like it.

Which are generated from the following, main.c:

include cairo.h (with # and <>)

int main()
{

    cairo_surface_t *surface =
        cairo_image_surface_create (CAIRO_FORMAT_ARGB32, 240, 80);
    cairo_t *cr =
        cairo_create (surface);

    cairo_select_font_face (cr, "serif", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
    cairo_set_font_size (cr, 32.0);
    cairo_set_source_rgb (cr, 0.0, 0.0, 1.0);
    cairo_move_to (cr, 10.0, 50.0);
    cairo_show_text (cr, "Hello, world");

    cairo_destroy (cr);
    cairo_surface_write_to_png (surface, "hello.png");
    cairo_surface_destroy (surface);

    return 0;
}

Any help fixing and understanding what's going on would be greatly appreciated. Thanks.

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1 Answer

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So the solution for this problem was as follows:

Use pkg-config for all the correct includes. Do so automatically by adding:

pkg-config --cflags --libs cairo (surrounded by " ` ", on the tilde key.)

to my "Other options" tab in the compiler settings.

I did the same for the linker "Other options" tab using:

pkg-config --libs cairo (also surrounded by " ` ", the accent grave)

Now I build and compile with no errors, but when I run it, I don't see anything but an empty console window : /


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