If like me you are unfortunate enough to live in an area not covered by *any* form of broadband access and must use a modem this script may help if you need to know your latest dynamically assigned IP. I've configured a NAT/Firewall server and need to let several people know the latest IP so they can log in. The $to address is assigned to a mailist but YMMV. Any comments welcome.
#!/usr/bin/perl -w
use strict;

my $from = "foo\@bar.com";
my $to = "bar\@foo.com";
my $subject = "Latest IP address";

my @ifc = `/sbin/ifconfig ppp0`;
chomp ($_ = $ifc[1]);
/inet\ addr:(\d+\.\d+\.\d+\.\d+)\s+.*$/;

open (MAIL, "|/usr/lib/sendmail -oi -t -odq") || die "Can't fork for s
+endmail: $!\n";
print MAIL "From: $from\nTo: $to\nSubject: $subject\n\n";
print MAIL $1;
close (MAIL);

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In reply to Getting the latest IP after dial-up by barrd

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