I understand that you want to pass filehandles to functions with the added feature that if user specified ...

Alas it seems I did not understand exactly. In my code above I assume that you will open a file using open my $fh, ... and that you pass around that filehandle and not a literal string/bareword representing also a filehandle, which gets complicated, having to specify also package names. So, in the code I provided the part open $fh, '>', 'xxx'; is essential. The following works for me:

{
package main;
my $fh = undef;
VRML::printout('some lines1', $fh);
open $fh, '>', 'xxx';
VRML::printout('some lines2', $fh);
close $fh;
}

{
package VRML;
sub printout {
  my ($lines, $_fh) = @_;
  my $fh = $_fh ? $_fh : *STDOUT;
  print $fh $lines;
}
}

[download]

bw, bliako

In reply to Re^3: Filehandle in subroutine in use VRML.pm by bliako
in thread Filehandle in subroutine in use VRML.pm by smittypaddler

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.