diff --git a/common/os_calls.c b/common/os_calls.c
index c964a9ff..a38eb396 100644
--- a/common/os_calls.c
+++ b/common/os_calls.c
@@ -93,7 +93,7 @@ g_init(const char* app_name)
   setlocale(LC_CTYPE, "");
   if (app_name != 0)
   {
-    if (app_name[0] == 0)
+    if (app_name[0] != 0)
     {
       snprintf(g_temp_base, sizeof(g_temp_base), "/tmp/%s-XXXXXX", app_name);
       if (mkdtemp(g_temp_base) == 0)