Check for the presence of sys/select.h and conditionally #include it.

patch by Michael Kostylev, mik niipt ru

Originally committed as revision 11324 to svn://svn.ffmpeg.org/ffmpeg/trunk

configure

@@ -718,6 +718,7 @@ HAVE_LIST="
     sdl_video_size
     soundcard_h
     sys_poll_h
+    sys_select_h
     sys_soundcard_h
     termios_h
     threads
@@ -1563,6 +1564,7 @@ enabled zlib && check_lib zlib.h zlibVersion -lz || disable zlib
 # if it's not found we can emulate it using select().
 if enabled ffserver; then
     check_header sys/poll.h
+    check_header sys/select.h
 fi
 
 # check for some common methods of building with pthread support

libavformat/os_support.c

@@ -29,7 +29,7 @@
 #ifndef HAVE_SYS_POLL_H
 #ifdef HAVE_WINSOCK2_H
 #include <winsock2.h>
-#else
+#elif defined (HAVE_SYS_SELECT_H)
 #include <sys/select.h>
 #endif
 #endif