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in C++ linux application, how can I get the network interface reffering to each IP on my machine? IP contains: static IP and dynamic IP

Note: I can't use the system call getnameinfo

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You can use the getifaddrs call; however, note that this only retrieves one address per interface. If that's not sufficient, use the rtnetlink protocol over a netlink socket; libnetlink may make this easier.

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getifaddrs() is implemented (on Linux) using netlink. It's the right interface (and it can return multiple addresses per interface - they just appear in multiple struct ifaddrs).
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It's quite tricky to do this, I believe you need to have root access. You need to issue an ioctl (something like SIOCGIFCONF) which then returns you a list of all interfaces, and then you can issue further ioctl calls to extract status information, etc.

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Neither is root needed, nor is SIOCGIFCONF a timely interface. Avoid.
stracing ip addr shows it using netlink sockets; and, of course, /bin/ip is not setuid :)
@user562374, I did say "I believe", not "it requires", the last time I did this was almost four years ago (but that was for capturing packets off of the interfaces - which did require root - hence the misconception), also, it is a valid mechanism for querying all interfaces on a box, it's not deprecated(?) so what's wrong with it?
SIGCGIFCONF won't return ipv6 addresses - and with the IANA pool depleted this is going to be a very important concern soon
@bdonlan, very true, definitely netlink if you've got ipv6 in your setup (but I'd hazard that most likely the OP's is on a private network, which is ipv4...) I've yet to encounter a private network that is using ipv6 though...

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