How can I determine if gnome_canvas_item_new() worked with a specified font?

[Antony Stace <antony claire co jp>]

Hi Folks
 
I need to know if a certain font exists on a computer.  I need to write
some text to a gnome canvas but want to check if the font exists before
I do it, if it doesnt then I want to use the default font on the
computer.  At present I have something like

item = gnome_canvas_item_new(rootGroup,
                      gnome_canvas_text_get_type(),
                      "text", "Test",
                      "x", (double) (30 ),
                      "y", (double) (85 ),
                      "fill_color", "black",
                      "font", 
                     
"-adobe-times-medium-r-normal-*-12-*-*-*-p-*-iso8859-1",
                      "anchor", GTK_ANCHOR_CENTER,
                       NULL);

If the font "-adobe-times-medium-r-normal-*-12-*-*-*-p-*-iso8859-1"
does not exist then I do not get anything displayed.  Is there anyway I
can check before hand to see if this font exists or else can I somehow
check the return code(  I currently do not know what the return code of
gnome_canvas_item_new() means).
Any help appreciated.

Cheers

Tony