Re: new wifi connection = nntp timeout = Emacs restart?

[Robert Pluim <rpluim@gmail.com>]

>>>>> On Mon, 04 May 2020 09:36:41 -0700, Eric Abrahamsen <eric@ericabrahamsen.net> said:

    >> Eric, are you on GNU/Linux? I can cook up a patch for that platform to
    >> try if you want.

    Eric> Yes, I'm on arch linux. I'd be happy to try this out. I'll be switching
    Eric> networks later this morning, if you've got something on hand already!

Be prepared for rather more network traffic when Gnus is idle.

diff --git a/src/process.c b/src/process.c
index 6e5bcf307a..fb0a20c797 100644
--- a/src/process.c
+++ b/src/process.c
@@ -38,6 +38,7 @@ Copyright (C) 1985-1988, 1993-1996, 1998-1999, 2001-2020 Free Software
 #include <sys/socket.h>
 #include <netdb.h>
 #include <netinet/in.h>
+#include <netinet/tcp.h>
 #include <arpa/inet.h>
 
 #endif	/* subprocesses */
@@ -3456,6 +3457,27 @@ connect_network_socket (Lisp_Object proc, Lisp_Object addrinfos,
 	    optbits |= set_socket_option (s, key, val);
 	  }
       }
+      if (!p->is_server && p->socktype != SOCK_DGRAM)
+        {
+          int optval;
+          int sz = sizeof(optval);
+          /* Enable keepalive.  */
+          optval = 1;
+          if (setsockopt (s, SOL_SOCKET, SO_KEEPALIVE, &optval, sz))
+            report_file_error ("socket keepalive 1", Qnil);
+          /* Set idle time.  */
+          optval = 1;
+          if (setsockopt (s, IPPROTO_TCP, TCP_KEEPIDLE, &optval, sz))
+            report_file_error ("socket keepalive 2", Qnil);
+          /* Time between keepalives.  */
+          optval = 1;
+          if (setsockopt (s, IPPROTO_TCP, TCP_KEEPINTVL, &optval, sz))
+            report_file_error ("socket keepalive 3", Qnil);
+          /* Number of probes.  */
+          optval = 2;
+          if (setsockopt (s, IPPROTO_TCP, TCP_KEEPCNT, &optval, sz))
+            report_file_error ("socket keepalive 4", Qnil);
+        }
 
       if (p->is_server)
 	{