You seem to be confused about the difference between command-line arguments and piping. If you say ls *.txt | ./myscript.pl, the STDOUT output of ls is going to STDIN of your script. Yet you are trying to get the names of those .txt files from @ARGV.

To actually get the filenames from the piped input, do something like: 

  chomp( my @filenames = <STDIN> );
  for (@filenames) {
    ... # open, read, etc
  }

[download]
A better solution for your particular example, though, is Zaxo's advice above. Use the -n option, or use the magic while (<>) loop: both automatically use the members of @ARGV as filenames and open them in sequence for you, reducing the code you've written to a one-liner.

Alternately, look at xargs to do something like this: 

  $ ls *.txt | xargs ./myscript.pl

[download]
.. which takes the name of each txt file (as given by ls) and passes it as a command-line argument (i.e, an element of @ARGV) to myscript.pl (plus or minus quoting/escaping issues)

blokhead

In reply to Re: command line pipe by blokhead
in thread command line pipe by pengyou_ah

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.