callback function help

[A R Hummaida <hummaida cs man ac uk>]

Dear all

i have a call back function that sets values to a globa struct. later 
another callback fuction
tries to read the values in this global struct, but the data in this 
struct (type gchar) is always either null or corupted.
how could go about solving this.i am using c and a lot of the code was 
generated using Glade.
help will be appreciated  

A .hummaida