progs/glsl: use ShadersSupported()
diff --git a/progs/glsl/texdemo1.c b/progs/glsl/texdemo1.c
index 5b1913a..2076e6a 100644
--- a/progs/glsl/texdemo1.c
+++ b/progs/glsl/texdemo1.c
@@ -400,11 +400,8 @@
 static void
 Init(GLboolean useImageFiles)
 {
-   const char *version = (const char *) glGetString(GL_VERSION);
-
-   if (version[0] != '2' || version[1] != '.') {
-      printf("Warning: this program expects OpenGL 2.0\n");
-      /*exit(1);*/
+   if (!ShadersSupported()) {
+      exit(1);
    }
    printf("GL_RENDERER = %s\n",(const char *) glGetString(GL_RENDERER));