diff --git a/libavformat/os_support.h b/libavformat/os_support.h
index 0b9fd49323..bc72e96a4c 100644
--- a/libavformat/os_support.h
+++ b/libavformat/os_support.h
@@ -57,6 +57,9 @@
 #endif
 
 #ifdef __ANDROID__
+#  if HAVE_UNISTD_H
+#    include <unistd.h>
+#  endif
 #  ifdef lseek
 #   undef lseek
 #  endif