LTTng » LTTng-tools

$ sudo -H lttng create sessionz -C net://131.132.32.77
Session sessionz created.
Error: You need both control and data URL.
Error: Command error
$ sudo -H lttng list
Available tracing sessions:
  1) sessionz () [inactive]

Use lttng list <session_name> for more details
$ sudo -H lttng list sessionz
Tracing session sessionz: [inactive]
    Trace path: 

$ sudo -H lttng start
Error: Can't find valid lttng config /root/.lttngrc
Did you create a session? (lttng create <my_session>)
Error: Command error
$ sudo -H lttng destroy sessionz
Session sessionz destroyed

This is because create.c's create_session calls _lttng_create_session_ext before checking if "was just one of -C and -D specified?":

if (opt_no_consumer) {
   [...]
} else if (opt_output_path != NULL) {
   [...]
} else if (opt_url) { /* Handling URL (-U opt) */
   [...]
} else if (opt_ctrl_url == NULL && opt_data_url == NULL) {
   [...]
}

ret = _lttng_create_session_ext(session_name, url, datetime);
if (ret < 0) {
   [...]
}

MSG("Session %s created.", session_name);
if (print_str_url) {
    MSG("Traces will be written in %s", print_str_url);
}

if (opt_ctrl_url && opt_data_url) {
   [...]
} else if ((!opt_ctrl_url && opt_data_url) ||
        (opt_ctrl_url && !opt_data_url)) {
    ERR("You need both control and data URL.");
    ret = CMD_ERROR;
    goto error;
}

That little block of code needs to be moved to the else if that precedes _lttng_create_session_ext.