--- a/src/core/ngx_connection.h
+++ b/src/core/ngx_connection.h
@@ -214,6 +214,7 @@ void ngx_close_connection(ngx_connection
 void ngx_close_idle_connections(ngx_cycle_t *cycle);
 ngx_int_t ngx_connection_local_sockaddr(ngx_connection_t *c, ngx_str_t *s,
     ngx_uint_t port);
+ngx_int_t ngx_tcp_nodelay(ngx_connection_t *c);
 ngx_int_t ngx_connection_error(ngx_connection_t *c, ngx_err_t err, char *text);
 
 ngx_connection_t *ngx_get_connection(ngx_socket_t s, ngx_log_t *log);