--- ./modules/stream_out/rtp.c.org	2009-07-21 09:29:16.787252342 +0200
+++ ./modules/stream_out/rtp.c	2009-07-21 09:30:11.003199471 +0200
@@ -1400,6 +1400,9 @@ static int FileSetup( sout_stream_t *p_s
     sout_stream_sys_t *p_sys = p_stream->p_sys;
     FILE            *f;
 
+    if( p_sys->psz_sdp == NULL )
+	    return VLC_EGENERIC; /* too early */
+
     if( ( f = utf8_fopen( p_sys->psz_sdp_file, "wt" ) ) == NULL )
     {
         msg_Err( p_stream, "cannot open file '%s' (%m)",