yet the code worked on the first run through (the error version with filehandles included) and not on subsequent iterations, but I'm happy it works.
You weren't using file handles. As already explained, you were using glob. And glob in scalar context acts as an iterator. The first time it's called, it returns the first match. The second time it's called, it returns the second match. And so on. When it's done, it returns undef. I've demonstrated that earlier in this thread.
The first time you called <$FH[$k]> (when $k==0), it returns the first result for $k==0.
The second time you called <$FH[$k]> (when $k==1), it returns the second result for $k==0 (undef).
but from then ($k>0) on I get an error that says "print() closed on filehandle OUT at isotopes-p7.perl line 14"
You told print to output to OUT (select (OUT);), but you closed OUT. Personally, I would remove the call to select and change
print "$BU[$i-1] $MA1[$i-1] $MA2[$i-1]\n";
print OUT "$BU[$i-1] $MA1[$i-1] $MA2[$i-1]\n";
I don't like using select. As you've encountered first hand, it introduces problems too easily.
Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
Want more info? How to link
or How to display code and escape characters
are good places to start.