What must I include to use GError

[Luis Velez <luis hpcf upr edu>]

Hi again,
In the reference manual it says that the only thing one must include in
order to use GError is glib.h but I include glib.h and all the other
libraries from the 'glib-config --cflags -- libs' but the GError data
type is not recognized by the compiler. Must I include another library?
It indicates that GError is undeclared. What version of glib.h must
I have? I have the version 1.2.10 of glib. Any sugestions about what
could be wrong are welcomed.