nginx 1.1.11 *) Feature: the "so_keepalive" parameter of the "listen" directive. Thanks to Vsevolod Stakhov. *) Feature: the "if_not_empty" parameter of the "fastcgi/scgi/uwsgi_param" directives. *) Feature: the $https variable. *) Feature: the "proxy_redirect" directive supports variables in the first parameter. *) Feature: the "proxy_redirect" directive supports regular expressions. *) Bugfix: the $sent_http_cache_control variable might contain a wrong value if the "expires" directive was used. Thanks to Yichun Zhang. *) Bugfix: the "read_ahead" directive might not work combined with "try_files" and "open_file_cache". *) Bugfix: a segmentation fault might occur in a worker process if small time was used in the "inactive" parameter of the "proxy_cache_path" directive. *) Bugfix: responses from cache might hang.

--- a/src/mail/ngx_mail.h
+++ b/src/mail/ngx_mail.h
@@ -40,6 +40,12 @@ typedef struct {
 #if (NGX_HAVE_INET6 && defined IPV6_V6ONLY)
     unsigned                ipv6only:2;
 #endif
+    unsigned                so_keepalive:2;
+#if (NGX_HAVE_KEEPALIVE_TUNABLE)
+    int                     tcp_keepidle;
+    int                     tcp_keepintvl;
+    int                     tcp_keepcnt;
+#endif
 } ngx_mail_listen_t;
 
 
@@ -95,6 +101,12 @@ typedef struct {
 #if (NGX_HAVE_INET6 && defined IPV6_V6ONLY)
     unsigned                ipv6only:2;
 #endif
+    unsigned                so_keepalive:2;
+#if (NGX_HAVE_KEEPALIVE_TUNABLE)
+    int                     tcp_keepidle;
+    int                     tcp_keepintvl;
+    int                     tcp_keepcnt;
+#endif
 } ngx_mail_conf_addr_t;