Re: CVS commit: src/sys/net

["M. Warner Losh" <imp%bsdimp.com@localhost>]

In message: <20090816184227.GB1436%ojctech.com@localhost>
            David Young <dyoung%pobox.com@localhost> writes:
: On Sun, Aug 16, 2009 at 05:01:12AM +0000, YAMAMOTO Takashi wrote:
: > hi,
: > 
: > > On Fri, Aug 14, 2009 at 06:48:10AM +0000, YAMAMOTO Takashi wrote:
: > >> hi,
: > >> 
: > >> > Module Name:   src
: > >> > Committed By:  dyoung
: > >> > Date:          Thu Aug 13 00:23:32 UTC 2009
: > >> > 
: > >> > Modified Files:
: > >> >        src/sys/net: if.c if.h
: > >> > 
: > >> > Log Message:
: > >> > Use sysctl(9) to expose to userland each interface transmission
: > >> > queue's maximum length, current length, and number of drops.  E.g.,
: > >> > 
: > >> > % sysctl net.interfaces.bnx0
: > >> > net.interfaces.bnx0.sndq.len = 0
: > >> > net.interfaces.bnx0.sndq.maxlen = 509
: > >> > net.interfaces.bnx0.sndq.drops = 0
: > >> 
: > >> does it work for xvif interfaces?  cf. PR/35074
: > > 
: > > Probably not.  Thanks for bringing this case to my attention.
: > > 
: > > I could change illegal characters in if_xname to dashes or to
: > > underscores in the sysctl node name.  Or I could name the node after the
: > > if_index instead of after the if_xname, if the if_xname contains illegal
: > > characters.  I guess that I like the latter idea better.  What do you
: > > think?
: > 
: > why do you want to use sysctl rather than eg. ioctl?
: 
: I like sysctl interfaces because they are self-describing, granular,
: hierarchical, and direct.  It is easy for userland to name sysctl
: interfaces to permit/restrict their visibility and use by a user or a
: process, and that is something I want to do in the future.

Plus, there's a generic sysctl manipulation program.  You don't have
that with an IOCTL.

Warner