diff --git a/src/main.cc b/src/main.cc
index 38f2b5d..f60159f 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -79,9 +79,15 @@ static Uint32 UpdateCallback(Uint32 interval, void * param)
 
 int main(int argc, char *argv[])
 {
+    if (argc != 2)
+    {
+        fprintf(stderr, "Usage: %s <font-file>\n", argv[0]);
+        return 1;
+    }
+
     if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER))
     {
-        printf("Failed to initialize SDL!\n");
+        fprintf(stderr, "Failed to initialize SDL!\n");
         return 1;
     }
 
@@ -95,7 +101,7 @@ int main(int argc, char *argv[])
                                            SDL_WINDOW_OPENGL);
     if (!window)
     {
-        printf("Failed to create window!\n");
+        fprintf(stderr, "Failed to create window!\n");
         SDL_Quit();
         return 2;
     }
@@ -104,12 +110,12 @@ int main(int argc, char *argv[])
 
     if (gl3wInit())
     {
-        cerr << "Failed to initialize GL3W" << endl;
+        fprintf(stderr, "Failed to initialize GL3W");
         return 2;
     }
     if (!gl3wIsSupported(3, 0))
     {
-        cerr << "OpenGL 3.0 is not supported!" << endl;
+        fprintf(stderr, "OpenGL 3.0 is not supported!");
         return 2;
     }