Sometimes it's useful to let Perl tell you what it thinks about the code you give it to execute (e.g., "where does the fourth lineread come from?"): 

>perl -MO=Deparse -ne
"$s=<>;<>;<>;chomp($s);print length($s).\"\n\";
"
LINE: while (defined($_ = <ARGV>)) {
    $s = <ARGV>;
    <ARGV>;
    <ARGV>;
    chomp $s;
    print length($s) . "\n";
}
-e syntax OK

[download]

Use  -MO=Deparse,-p for even gorier details. See B::Deparse and O.

In reply to Re: command line perl reading from STDIN by AnomalousMonk
in thread command line perl reading from STDIN by perlhappy

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