manager: include full systemctl status command line in error message

TODO

@@ -80,6 +80,8 @@ Features:
 
 * In systemctl make sure both is-enabled and is-active print a string, or neither.
 
+* teach systemctl to enable unit files in arbitrary directories
+
 * when failing to start a service due to ratelimiting, try again later, if restart=always is set
 
 * write blog stories about:

src/manager.c

@@ -1468,9 +1468,10 @@ static int transaction_add_job_and_dependencies(
         if (type != JOB_STOP && unit->meta.load_state == UNIT_ERROR) {
                 dbus_set_error(e, BUS_ERROR_LOAD_FAILED,
                                "Unit %s failed to load: %s. "
-                               "See system logs and 'systemctl status' for details.",
+                               "See system logs and 'systemctl status %s' for details.",
                                unit->meta.id,
-                               strerror(-unit->meta.load_error));
+                               strerror(-unit->meta.load_error),
+                               unit->meta.id);
                 return -EINVAL;
         }