Fix: Warn if session is running with lttng view

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

diff --git a/src/bin/lttng/commands/view.c b/src/bin/lttng/commands/view.c
index 9508743e62878ade2428905ba0bfdc9e831537f5..dd3c9a3cc225b06d2ff055fdfb7acdfe0bc141ef 100644 (file)
--- a/src/bin/lttng/commands/view.c
+++ b/src/bin/lttng/commands/view.c
@@ -88,6 +88,7 @@ static void usage(FILE *ofp)
        fprintf(ofp, "Where SESSION_NAME is an optional session name. If not specified, lttng will\n");
        fprintf(ofp, "get it from the configuration file (.lttngrc).\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, "  -t, --trace-path PATH    Trace directory path for the viewer\n");
@@ -342,6 +343,13 @@ static int view_trace(void)
                trace_path = opt_trace_path;
        }
 
+       if (sessions[i].enabled) {
+               WARN("Session %s is running. Please stop it before reading it.",
+                               session_name);
+               ret = CMD_ERROR;
+               goto free_sessions;
+       }
+
        MSG("Trace directory: %s\n", trace_path);
 
        ret = spawn_viewer(trace_path);