Dear Monks - I am novice asking for help or advice please;
To modify a text file by adding one extra line spacing between each line, I initially hardcoded the name of target file... 3.txt into my code.

How to revise so that ANY file can be used (ie. perl myprogram.pl anyfile.txt) from the command line?
I have started to read about IO::Handles ... would you recommended that or please say what would be a better method for this problem? 


open(PAGE,"3.txt") || die "I can't open yourfile.txt";

@File =<PAGE> ;  #store the contents of the file into array
close(PAGE);
$Ctr = 0;

foreach (@File){     # loop through file
{
$_ = $_ . "\n" #add extra newline to each line
}
$Ctr = $Ctr+1; #increment through the array
} #end foreach

open(PAGE,">3.txt") || die "I can't open yourfile.txt";   #write the a
+rray contents
print PAGE @File;
close(PAGE);

[download]

In reply to IO::Handles ... any good? by blowupp

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.