open (READ, "ifconfig fxp0 |") or die "$!";
while (<READ>) {
     chomp;
     if (/ether/) {
          s/^\s+//;
          my $mac = (split)[1];
     }
}
close READ;
[download]

update: arp gets the MAC address of the gateway or router of your network. I should just shut up.

Same basic idea for Win NT/2000 except you would use 'arp -a' what Rex(Wrecks) says in place of the ifconfig read

arp -a is not that good as you get the entire arp cache. ipconfig /all is much better as it allows you to parse data per interface.

I guess this is TIMTOWTDI, but using ipconfig /all allows you to write a reusable sub that returns all of the parsed data for you, and allows you to pick and choose which of that data you want to use. I guess I'm lazy and just do all the work up front and never have to deal with it again :)

"Nothing is sure but death and taxes" I say combine the two and its death to all taxes!

A better solution might be to look at the IO::Interface module as I have suggested here - The reason for this is the dependency on the external binary which your code introduces. This dependency could easily render your code unworkable if the output structure from ifconfig is modified significantly - Also too, as you have not specified a full path to the binary, it would be quite easy for someone with malicious intent to change the path environment and introduce their own ifconfig which could generate some very unexpected and most unwanted results within your code.

I have rambled on this topic previously here.

 

perl -e 's&&rob@cowsnet.com.au&&&split/[@.]/&&s&.com.&_&&&print'

use IO::Socket;
use IO::Interface qw(:flags);

my $s = IO::Socket::INET->new(Proto => 'udp');
my @interfaces = $s->if_list;

for my $f (@interfaces) {
    print "interface = $if\n";
    my $flags = $s->if_flags($if);
    print "addr =      ",$s->if_addr($if),"\n",
        "broadcast = ",$s->if_broadcast($if),"\n",
        "netmask =   ",$s->if_netmask($if),"\n",
        "dstaddr =   ",$s->if_dstaddr($if),"\n",
        "hwaddr =    ",$s->if_hwaddr($if),"\n";


    print "is running\n"     if $flags & IFF_RUNNING;
    print "is broadcast\n"   if $flags & IFF_BROADCAST;
    print "is p-to-p\n"      if $flags & IFF_POINTOPOINT;
    print "is loopback\n"    if $flags & IFF_LOOPBACK;
    print "is promiscuous\n" if $flags & IFF_PROMISC;
    print "is multicast\n"   if $flags & IFF_MULTICAST;
    print "is notrailers\n"  if $flags & IFF_NOTRAILERS;
    print "is noarp\n"       if $flags & IFF_NOARP;
}
[download]

If all that you are looking for is the MAC address of the interface card, then the $obj->if_hwaddr method is all you will need to worry about.

perl -e 's&&rob@cowsnet.com.au&&&split/[@.]/&&s&.com.&_&&&print'

Yep, this works really well, so I will be able to start coding. Thanks to everyone that offered suggestions. I didn't want to use an external program unless there was no other way. I'll post a snippet when I have something finished.
There is a small typo though -

for my $f (@interfaces) {
[download]

should be:

for my $if (@interfaces) {
[download]

otherwise nothing prints out..

Mildew Hall.. Home of PurePostPro and other Perl goodies!
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