> -----Original Message----- > From: Stephen Hemminger [mailto:step...@networkplumber.org] > Sent: Wednesday, April 26, 2017 11:08 PM > To: Zhang Shengju <zhangshen...@cmss.chinamobile.com> > Cc: netdev@vger.kernel.org > Subject: Re: [iproute2] iplink: add support for IFLA_CARRIER attribute > > On Wed, 26 Apr 2017 15:08:39 +0800 > Zhang Shengju <zhangshen...@cmss.chinamobile.com> wrote: > > > Add support to set IFLA_CARRIER attribute. > > > > Signed-off-by: Zhang Shengju <zhangshen...@cmss.chinamobile.com> > > --- > > ip/iplink.c | 12 ++++++++++++ > > 1 file changed, 12 insertions(+) > > > > diff --git a/ip/iplink.c b/ip/iplink.c index 866ad72..263bfdd 100644 > > --- a/ip/iplink.c > > +++ b/ip/iplink.c > > @@ -72,6 +72,7 @@ void iplink_usage(void) > > " [ allmulticast { on | off } ]\n" > > " [ promisc { on | off } ]\n" > > " [ trailers { on | off } ]\n" > > + " [ carrier { on | off } ]\n" > > " [ txqueuelen PACKETS ]\n" > > " [ name NEWNAME ]\n" > > " [ address LLADDR ]\n" > > @@ -673,6 +674,17 @@ int iplink_parse(int argc, char **argv, struct > iplink_req *req, > > req->i.ifi_flags |= IFF_NOARP; > > else > > return on_off("arp", *argv); > > + } else if (strcmp(*argv, "carrier") == 0) { > > + int carrier; > > + NEXT_ARG(); > > + if (strcmp(*argv, "on") == 0) > > + carrier = 1; > > + else if (strcmp(*argv, "off") == 0) > > + carrier = 0; > > + else > > + return on_off("carrier", *argv); > > + > > + addattr8(&req->n, sizeof(*req), IFLA_CARRIER, > carrier); > > } else if (strcmp(*argv, "vf") == 0) { > > struct rtattr *vflist; > > > > The general policy of ip link command is all options should be invertable. Yes, so I add 'on' and 'off' subcommand to make sure that it can be invertable.
> There are some VPN's that use this to save and restore state. So if you add > an option to set something there should be similar output under the detailed > show command. Currently, "show command" already can display 'carrier' status. Such as: dummy0: <NO-CARRIER...>
