print err msg if unable to open shader file

diff --git a/progs/util/shaderutil.c b/progs/util/shaderutil.c
index 4f17dd7..7458513 100644 (file)
--- a/progs/util/shaderutil.c
+++ b/progs/util/shaderutil.c
@@ -80,6 +80,7 @@ CompileShaderFile(GLenum shaderType, const char *filename)
 
    FILE *f = fopen(filename, "r");
    if (!f) {
+      fprintf(stderr, "Unable to open shader file %s\n", filename);
       return 0;
    }