If you run your script on Windows, the carrage return and newline will both be removed (since it's expected that under Windows files will end in both a carriage return and a newline).

That's completely wrong. Perl automatically converts CRLF to LF when reading text, so $/ is set to LF ("\n"). Your script shouldn't see CR at all, so chomp only removes the LF.

Now, if you were dealing with binary data, chomp won't work (without changing $/) because chomp is a text function. 

print(unpack('H*', $/), "\n");    # 0a          Just LF

my $str = <DATA>;
print(unpack('H*', $str), "\n");  # 746573740a  No CR

chomp($str);
print(unpack('H*', $str), "\n");  # 74657374    LF chomped.

__DATA__
test

[download]

If, on the other hand, you want to run a script that will strip the EOL marker off a file regardless of what OS the script is running on and whether that file came from Unix or Windows, you need to do that yourself, with something like:

That regexp is incomplete. It doesn't handle systems that use \r as the EOL marker.

In reply to Re^2: chomp() is confusing by ikegami
in thread Why chomp() is not considering carriage-return by jesuashok

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.