diff --git a/libavformat/os_support.c b/libavformat/os_support.c
index 5427c567e6..795fab884b 100644
--- a/libavformat/os_support.c
+++ b/libavformat/os_support.c
@@ -103,6 +103,7 @@ done:
 }
 #endif /* !defined(HAVE_INET_ATON) && defined(CONFIG_NETWORK) */
 
+#ifdef CONFIG_FFSERVER
 #ifndef HAVE_SYS_POLL_H
 int poll(struct pollfd *fds, nfds_t numfds, int timeout)
 {
@@ -161,7 +162,6 @@ int poll(struct pollfd *fds, nfds_t numfds, int timeout)
 
     return rc;
 }
-
-
 #endif /* HAVE_SYS_POLL_H */
+#endif /* CONFIG_FFSERVER */
 
diff --git a/libavformat/os_support.h b/libavformat/os_support.h
index 34c2fabcd3..9d7ab4c7bb 100644
--- a/libavformat/os_support.h
+++ b/libavformat/os_support.h
@@ -75,6 +75,7 @@ static inline int strcasecmp(const char* s1, const char* s2) { return stricmp(s1
 #define closesocket close
 #endif
 
+#ifdef CONFIG_FFSERVER
 #ifndef HAVE_SYS_POLL_H
 typedef unsigned long nfds_t;
 
@@ -101,5 +102,6 @@ struct pollfd {
 
 extern int poll(struct pollfd *fds, nfds_t numfds, int timeout);
 #endif /* HAVE_SYS_POLL_H */
+#endif /* CONFIG_FFSERVER */
 
 #endif /* _OS_SUPPORT_H */