diff --git a/src/os/unix/ngx_recv.c b/src/os/unix/ngx_recv.c
index b8a9659..37e70c6 100644
--- a/src/os/unix/ngx_recv.c
+++ b/src/os/unix/ngx_recv.c
@@ -6,7 +6,7 @@
 
 #if (HAVE_KQUEUE)
 
-ssize_t ngx_unix_recv(ngx_connection_t *c, char *buf, size_t size)
+ssize_t ngx_unix_recv(ngx_connection_t *c, u_char *buf, size_t size)
 {
     ssize_t       n;
     ngx_err_t     err;