topic TCPIP KeepAlive in Operating System - OpenVMS

TCPIP KeepAlive

Mark Battle — Thu, 10 Apr 2008 08:41:04 GMT

How do I use the KeepAlive option, from a C program, to prevent a TCPIP connection from disconnecting when there is no traffic for a long time?
There used to be a good site from Digital about TCPIP, but I can't find it anymore.

Re: TCPIP KeepAlive

labadie_1 — Thu, 10 Apr 2008 09:04:04 GMT

It seems it is in the doc

http://h71000.www7.hp.com/doc/73final/6529/6529pro_022.html

Appendix A
Socket Options
This appendix describes the socket options that you can set with theSockets APIsetsockopt() function and the $QIO system service IO$_SETMODE and IO$_SETCHAR I/O function codes. You can query the value of these socket options using the Sockets APIgetstockopt() function or the $QIO system service IO$_SENSEMODE or IO$_SENSECHAR I/O function code.

Re: TCPIP KeepAlive

labadie_1 — Thu, 10 Apr 2008 09:28:03 GMT

In tcpip$examples, you can find some C programs, among them

SYS$COMMON:[SYSHLP.EXAMPLES.TCPIP]TCPIP$TCP_SERVER_QIO.C;1

shows
* 1) To create a socket and set REUSEADDR option:

Not keepidle, but an example on how to set an option on a socket.

For the website, I guess you were looking for
http://askq.compaq.com

which is now redirected, and I can't find anything with it.

I hope all the good articles
Example-C How to...
and
Example-Basic and many others
are not lost

Re: TCPIP KeepAlive

Jim_McKinney — Thu, 10 Apr 2008 12:09:02 GMT

After you've created your socket, the call should be something like the hollowing:

struct tcp_keepalive {
int idle_time; /* Idle time before first probe */
int probe_intvl; /* Time between probes */
int probe_count; /* Number of probes before closing connection */
};

Status = setsockopt(socket, IPPROTO_TCP, TCP_KEEPALIVE,
&keepalive, sizeof(keepalive));

Re: TCPIP KeepAlive

Mark Battle — Fri, 11 Apr 2008 09:12:31 GMT

Great. Now it works. Thanks