while (<DATA>) {
    print "$_\n" for /(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}:\d{1,4})/gi;
}

__DATA__
some stuff 10.0.0.1:80 stuff
127.0.0.1:22 more stuffs 10.2.2.8:8080
nothing here
3.4.5.6:1 100.200.100.200:3000
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You can change the code to following, save it to file named script.pl and run it like so: perl script.pl < file.txt

use strict;
use warnings;
while (<>) {
    print "$_\n" for /(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}:\d{1,4})/gi;
}
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