How do I set the color and font of a GtkLabel using a Resource File?

The widget name path constructed for a Label consists of the widget names of its object hierarchy as well, e.g.

window (name: humphrey)
hbox
label (name: mylabel)

The widget path your pattern needs to match would be: humphrey.GtkHBox.mylabel

The resource file may look something like:

style "title"
{
      fg[NORMAL] = {1.0, 0.0, 0.0}
      font = "-adobe-helvetica-bold-r-normal--*-140-*-*-*-*-*-*"
}
widget "*mylabel" style "title"

In your program, you would also need to give a name to the Label widget, which can be done using:

  label = gtk_label_new("Some Label Text");
  gtk_widget_set_name(label, "mylabel");
  gtk_widget_show(label);