string.h is a system header file, so use <> for it.

Originally committed as revision 13091 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/apc.c

@@ -19,8 +19,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <string.h>
 #include "avformat.h"
-#include "string.h"
 
 static int apc_probe(AVProbeData *p)
 {