PJ_DEF(pj_status_t) pjsip_ua_destroy(void)
{
    /* Check if module already destroyed. */
    PJ_ASSERT_RETURN(mod_ua.mod.id != -1, PJ_EINVALIDOP);

    return pjsip_endpt_unregister_module(mod_ua.endpt, &mod_ua.mod);
}
PJ_DEF(pj_status_t) pjsip_ua_destroy(void)
{
     
    PJ_ASSERT_RETURN(mod_ua.mod.id != -1, PJ_EINVALIDOP);

    return pjsip_endpt_unregister_module(mod_ua.endpt, &mod_ua.mod);
}