Date: Mon, 13 Dec 2004 23:26:57 +0100 From: Michal Mertl <mime@traveller.cz> To: freebsd-net@freebsd.org Subject: extending ifmib(4) and de-mem(4)izing netstat Message-ID: <41BE1731.8070902@traveller.cz>
next in thread | raw e-mail | index | archive | help
Hello all, I like the idea of a system without mem(4) but some system utilities depend on it. I thought I would go and change them to use other ways to get the information. I started with 'netstat -r' and almost completely (refcnt field is missing) removed the need for /dev/mem (in fact there already was incomplete support for it in the sources). I then went to reimplement 'netstat -i' and found out I can't get all the information from sysctls. The stats which I can't find are the counters for addresses configured on the interfaces (in kernel stored in struct in_ifaddr). Am I missing something or would I have to export the data from the kernel? What is the best way to export them? I can see two ways: make it accessible like if_data is exported for physical interfaces in getifaddrs(3) or export the data into some other place like ifmib(4) - e.g. net.inet.generic and net.inet6.generic. From getifaddrs.c I can see that one way to add the information would be to implement something called ifam_data (probably in fact struct ifam_msghdr) which is present on BSDI. It would probably be also possible to hack it rather easily into sysctl_iflist (src/sys/net/rtsock.c) a-la ifm_data member of struct if_msghdr. P.S.: It was a great adventure to browse through the code trying to understand what it does. Did humans write it? :-) I'm talking about the data structures in the kernel, netstat sources are on the other hand a mess. -- Michal Mertl
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?41BE1731.8070902>