Add lttng-error.h containing every API err. code

[lttng-tools.git] / src / bin / lttng / commands / start.c

diff --git a/src/bin/lttng/commands/start.c b/src/bin/lttng/commands/start.c
index 0f44f4cdac511a750d884546cc65d6a96001d52f..82122cc63a464b09642ba6faa7cc1e2a9c3c6042 100644 (file)
--- a/src/bin/lttng/commands/start.c
+++ b/src/bin/lttng/commands/start.c
@@ -26,6 +26,8 @@
 
 #include "../command.h"
 
+#include <common/sessiond-comm/sessiond-comm.h>
+
 static char *opt_session_name;
 
 enum {
@@ -45,11 +47,12 @@ static struct poptOption long_options[] = {
  */
 static void usage(FILE *ofp)
 {
-       fprintf(ofp, "usage: lttng start [options] [NAME]\n");
+       fprintf(ofp, "usage: lttng start [NAME] [OPTIONS]\n");
        fprintf(ofp, "\n");
        fprintf(ofp, "Where NAME is an optional session name. If not specified, lttng will\n");
        fprintf(ofp, "get it from the configuration directory (.lttng).\n");
        fprintf(ofp, "\n");
+       fprintf(ofp, "Options:\n");
        fprintf(ofp, "  -h, --help               Show this help\n");
        fprintf(ofp, "      --list-options       Simple listing of options\n");
        fprintf(ofp, "\n");
@@ -79,7 +82,14 @@ static int start_tracing(void)
 
        ret = lttng_start_tracing(session_name);
        if (ret < 0) {
-               /* Don't set ret so lttng can interpret the sessiond error. */
+               switch (-ret) {
+               case LTTNG_ERR_TRACE_ALREADY_STARTED:
+                       WARN("Tracing already started for session %s", session_name);
+                       break;
+               default:
+                       ERR("%s", lttng_strerror(ret));
+                       break;
+               }
                goto free_name;
        }