getifaddrs return same adapter multiple times

[wwwnuwan]

Hi,
I have written a c program to retrieve all the network interfaces.

getifaddrs(&ifaddr)

But when I iterate through the ifaddr elements of the linklist it returns same interface many times. When I prints the ifa_name s it prints like as follow.

lo
eth0 *
irda0
wmaster0
wlan0
pan0
lo
eth0 *
lo
eth0 *

* - repeats

I want to eliminate this repeating and need to retrieve the address that return with ifconfig -a command.
How can I overcome this ?

when I command $ifconfig -a its list as follows.

eth0 Link encap:Ethernet

irda0 Link encap:IrLAP

lo Link encap:Local

pan0 Link encap:Ethernet

wlan0 Link encap:Ethernet

wmaster0 Link encap:UNSPEC


Thank you very much.

Reg,
Nuwan Gunarathne

[cas]

If this is on Linux, look at the NOTES section of the getifaddrs() man page:

The addresses returned on Linux will usually be the IPv4 and IPv6 addresses assigned to the interface, but also one AF_PACKET address per interface containing lower-level details about the interface and its physical layer. In this case, the ifa_data field may contain a pointer to a struct net_device_stats, defined in <linux/netdevice.h>, which contains various interface attributes and statistics.

That's probably where the multiple interfaces are coming from. You should be able to filter these by looking at ifa_addr->sa_family.