The easy fix is to use print instead of printf. See also the documentation of printf, which says:

Don't fall into the trap of using a printf when a simple print would do. The print is more efficient and less error prone.

I'm not sure why printf has this problem, but it seems to fatally dislike that you pass it strings with arguments to be interpolated (%) where there is nothing to interpolate. I'm not sure that it should choke on this. I won't provide you the "other easy" fix for this, because you should use print instead if you want to output a simple string.

You should also indent your code properly, not clobber NFILE (or even better, use lexical filehandles) and check whether open fails:

use strict;

sub CreateConfig{
    my ($file,@data) = @_;
    $file = $file.".new";
    local *NFILE;
    open(NFILE,">$file") or die "Couldn't create '$file': $!";
    foreach my $item (@data){
        print NFILE "$item\n";
    };
    close(NFILE);
}

CreateConfig('test.cfg','passwd chat = *New*UNIX*password* %n\n *ReTyp
+e*new*UNIX*password* %n\n *passwd:*all*authentication*tokens*updated*
+successfully*');

[download]

In reply to Re: Escaping special chars to add in a file by Corion
in thread Escaping special chars to add in a file by Anonymous Monk

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.