--- a/src/os/unix/ngx_os.h
+++ b/src/os/unix/ngx_os.h
@@ -17,7 +17,8 @@
 
 
 typedef ssize_t (*ngx_recv_pt)(ngx_connection_t *c, u_char *buf, size_t size);
-typedef ssize_t (*ngx_recv_chain_pt)(ngx_connection_t *c, ngx_chain_t *in);
+typedef ssize_t (*ngx_recv_chain_pt)(ngx_connection_t *c, ngx_chain_t *in,
+    off_t limit);
 typedef ssize_t (*ngx_send_pt)(ngx_connection_t *c, u_char *buf, size_t size);
 typedef ngx_chain_t *(*ngx_send_chain_pt)(ngx_connection_t *c, ngx_chain_t *in,
     off_t limit);
@@ -41,7 +42,7 @@ ngx_int_t ngx_os_signal_process(ngx_cycl
 
 
 ssize_t ngx_unix_recv(ngx_connection_t *c, u_char *buf, size_t size);
-ssize_t ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *entry);
+ssize_t ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *entry, off_t limit);
 ssize_t ngx_udp_unix_recv(ngx_connection_t *c, u_char *buf, size_t size);
 ssize_t ngx_unix_send(ngx_connection_t *c, u_char *buf, size_t size);
 ngx_chain_t *ngx_writev_chain(ngx_connection_t *c, ngx_chain_t *in,
@@ -49,7 +50,7 @@ ngx_chain_t *ngx_writev_chain(ngx_connec
 
 #if (NGX_HAVE_AIO)
 ssize_t ngx_aio_read(ngx_connection_t *c, u_char *buf, size_t size);
-ssize_t ngx_aio_read_chain(ngx_connection_t *c, ngx_chain_t *cl);
+ssize_t ngx_aio_read_chain(ngx_connection_t *c, ngx_chain_t *cl, off_t limit);
 ssize_t ngx_aio_write(ngx_connection_t *c, u_char *buf, size_t size);
 ngx_chain_t *ngx_aio_write_chain(ngx_connection_t *c, ngx_chain_t *in,
     off_t limit);