ngx_socket_n      315 core/ngx_connection.c                               ngx_socket_n " %V failed", &ls[i].addr_text);
ngx_socket_n     2117 core/ngx_resolver.c                       ngx_socket_n " failed");
ngx_socket_n       35 event/ngx_event_connect.c                       ngx_socket_n " failed");