It says the keyword gets parsed, but then does performs no action. But that is different from not parsing it.
Additionally, this explains an option which other systems support, and by explaining it this way, it is also explaining our behaviour in case of inet6 vs inet4 conditions. So... I think it should stay. Eric, do you have an opinion? > Is there a reason to keep this part in resolv.conf(5) about an option > doing nothing? > > > options inet6 > > Enables support for IPv6-only applications, by setting RES_USE_INET6 > > in _res.options (see res_init(3)). On OpenBSD this option does > > nothing. > > If we can remove it, here is the diff. > > Index: resolv.conf.5 > =================================================================== > RCS file: /home/cvs/src/share/man/man5/resolv.conf.5,v > retrieving revision 1.59 > diff -u -p -r1.59 resolv.conf.5 > --- resolv.conf.5 24 Jan 2020 06:16:47 -0000 1.59 > +++ resolv.conf.5 23 Apr 2020 15:09:42 -0000 > @@ -258,13 +258,6 @@ particularly if there is a reduced MTU, > as is often the case with > .Xr pppoe 4 > or with tunnels. > -.It Cm inet6 > -Enables support for IPv6-only applications, by setting RES_USE_INET6 in > -_res.options (see > -.Xr res_init 3 ) . > -On > -.Ox > -this option does nothing. > .It Cm insecure1 > Do not require IP source address on the reply packet to be equal to the > server's address. >
