[linux] How do you find out which version of GTK+ is installed on Ubuntu?

You could also just compile the following program and run it on your machine.

#include <gtk/gtk.h>
#include <glib/gprintf.h>

int main(int argc, char *argv[])
{
    /* Initialize GTK */
    gtk_init (&argc, &argv);

    g_printf("%d.%d.%d\n", gtk_major_version, gtk_minor_version, gtk_micro_version);
    return(0);
}

compile with ( assuming above source file is named version.c):

gcc version.c -o version `pkg-config --cflags --libs gtk+-2.0`

When you run this you will get some output. On my old embedded device I get the following:

[root@n00E04B3730DF n2]# ./version 
2.10.4
[root@n00E04B3730DF n2]#