IFF_LINKDOWN and Carrier Detect

Josh Birnbaum · *nix forums beginner Joined: 02 Apr 2005 Posts: 25

Hi Folks,

Does anyone have any sample code to detect that a network link
has gone down? syslogd on my Indy R5000 running IRIX 6.5.22m
writes the following to /var/adm/SYSLOG in such situations:

Feb 24 02:56:17 1A:IRIS unix: |$(0xd3)ALERT: ec0: no carrier: \
check Ethernet cable

I was looking through /usr/include and found the IFF_LINKDOWN
define directive in net/if.h. I tried passing this to ioctl(2)
after having passed the SIOCGIFFLAGS command to a previous
ioctl(2) call but no go.
Additional probing has me thinking that IFF_LINKDOWN is not
what I'm after.

Any info re the above would be appreciated.

Thanks,

Josh.

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