FAQ 9.22 How do I read mail?

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This is an excerpt from the latest version perlfaq9.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .


9.22: How do I read mail?

    While you could use the "Mail::Folder" module from CPAN (part of the
    "MailFolder" package) or the "Mail::Internet" module from CPAN (part of
    the "MailTools" package), often a module is overkill. Here's a mail


            my(@msgs, @sub);
            my $msgno = -1;
            $/ = '';                    # paragraph reads
            while (<>) {
                    if (/^From /m) {
                            $sub[++$msgno] = lc($1) || '';
                    $msgs[$msgno] .= $_;
            for my $i (sort { $sub[$a] cmp $sub[$b] || $a <=> $b } (0 ..
$#msgs)) {
                    print $msgs[$i];

    Or more succinctly,

            #!/usr/bin/perl -n00
            # bysub2 - awkish sort-by-subject
            BEGIN { $msgno = -1 }
            $sub[++$msgno] = (/^Subject:\s*(?:Re:\s*)*(.*)/mi)[0] if /^From/m;
            $msg[$msgno] .= $_;
            END { print @msg[ sort { $sub[$a] cmp $sub[$b] || $a <=> $b } (0 ..
$#msg) ] }


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