updating background pixmap

[Martin Craig <mcra98 esc cam ac uk>]

Dear All,

I have a text widget with a changing background pixmap, but I can't
figure out how to
make it update. I've tried various combinations of gdk_flush,
gtk_main_iteration, 
gtk_editable_changed, & also tried (failed) to send the ExposeEvent
signal (not that this
is likely to work since exposing doesn't always cause an update). Is
there a foolproof
way of making this happen?

Thanks, Martin.