A.pressed B.released C.clicked D.enter
A.gcc -o ex ex.c gtk-config -cflags --libs B.gcc -o ex ex.c ’gtk-config -cflags -libs’ C.gcc -o ex ex.c ’gtk-config -cflags -libs D.gcc -o ex ex.c "gtk-config -cflags -libs"
A.gtk_init B.gtk_windows_new C.gtk_widget_show D.gtk_main