Hi, guys! I must issue a system call from my program, something like system ("prog"); This operation takes at least a minute, but the time of computation actually depends on many parameters. 1) How do I keep refreshing the GUI? while (gtk_events_pending) obviously won't work, I also tried it this way: timeout = gtk_timeout_add (100, test, NULL); system ("prog"); gtk_timeout_remove (timeout); but this doesn't work either. What do I do? 2) Connected to 1): I need a progress bar for this system call. How do I create it if I can't reach gtk_main ()? Thanks, Andrej