Subject: Re: add new sysctl parameter
To: Zongsheng Zhang <>
From: Andrew Brown <>
List: tech-kern
Date: 12/14/2004 09:13:31
>Does someone know how to add a new sysctl parameter?
>I like to add a tcp-level sysctl parameter to control my own function.
>I have tried to modify /sys/netinet/tcp_var.h, tcp_subr.c and
>/usr/include/netinet/tcp_var.h, then re-compile sysctl command.
>But it seems not work, I can't see my new sysctl var with sysctl.

it should suffice for you to modify tcp_usrreq.c, recompile your
kernel, and reboot.  the sysctl bianry should not need to be rebuilt.

>Could you give me a guide?

see sysctl(9) and tcp_usrreq.c (among others).

|-----< "CODE WARRIOR" >-----|             * "ah!  i see you have the internet (Andrew Brown)                that goes *ping*!"       * "information is power -- share the wealth."