Hi,
I was using yahoo today where I was going to post a message. I "signed on" and there was this message reminding me that they know what my IP address is and displayed it. How do they do that?

If I wrote a cgi like so ... 

#!/bin/perl

print "Content-type:text/html\n\n";
for $var ( keys %ENV ) {
print "<br>$var = $ENV{$var}\n";
}

[download]

would I see my IP address in the resulting html?

Thanks
Alien

2001-11-03 Edit by Corion : Added CODE tags and formatting

In reply to How do I get someone's IP address? by AlienAcrobatic

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