From c55e00fe59408dcfb461313336c49e3ae5805df0 Mon Sep 17 00:00:00 2001
From: Sam Hocevar <sam@hocevar.net>
Date: Sat, 12 Nov 2005 15:30:46 +0000
Subject: [PATCH]   * src/caca.c: on Unix, do not use the GL driver if DISPLAY
 is not set.

---
 src/caca.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/caca.c b/src/caca.c
index 13afa46..e8ba95e 100644
--- a/src/caca.c
+++ b/src/caca.c
@@ -533,8 +533,13 @@ static void caca_init_driver(void)
     }
 #endif
 #if defined(USE_GL)
-    _caca_driver = CACA_DRIVER_GL;
-    return;
+#if defined(HAVE_GETENV) && defined(GLUT_XLIB_IMPLEMENTATION)
+    if(getenv("DISPLAY") && *(getenv("DISPLAY")))
+#endif
+    {
+        _caca_driver = CACA_DRIVER_GL;
+        return;
+    }
 #endif
 #if defined(USE_SLANG)
     _caca_driver = CACA_DRIVER_SLANG;