Question

I have a .txt file with many emails including headers. I’m just wondering how I would use perl to find out how many occurrences of the same email address are found in this text file?
Would it involve regular expressions?

Answer 1

How about this script:

#!/usr/bin/perl

use strict;
use Data::Dumper;

my @email_list = ();
my %count;

while (my $line = <>) {
    foreach my $email (split /\s+/, $line) {
        if ( $email =~ /^[-\w.]+@([a-z0-9][a-z-0-9]+\.)+[a-z]{2,4}$/i ) {

            push(@email_list,$email);
        }
    }
}

print "Total Email Count: ".scalar(@email_list)."\n\n";
$count{$_}++ for @email_list;
print Dumper(\%count);

Save it to a file such as email.pl and make sure it executable chmod +x email.pl.

./email.pl file.txt

It will print the total number of email addresses found and count per email address.