I really wish you would have included some sample data - it doesn't have to be the exact data for obvious legal reasons, but just some data of similar structure. This code is quite horrible, it is obvious that someone was attempting to make modular, reusable code, but fell short of the mark.

Looks like the idea is to sort on the results of a user defined sort routine (that relies on global variable no less) that gets its input from a subroutine that turns its first argument into a filehandle and returns it. This is wrong, wrong, wrong, wrong!

Instead, you should open the file, process it into a data structure - looks like a 2-d array would be good to me, THEN sort the data structure. The subroutine sort_func is repeatedly splitting the lines to do it's work - this is extremely wasteful, especially if you need the pieces of the lines again later on.

Here is some sample code to play with. Since you didn't supply any test data (hint hint), i'll make up my own. Also, i am going to use the DATA handle instead of reading from a file. You should have no troubles changing this to fit your needs:

use strict;

my $datafields = 3;
my $item_no    = 2;
my @records;

# read from DATA - any filehandle will do . . .
foreach my $line (<DATA>) {
   chomp $line;
   push @records, [ split(/\s+/,$line,$datafields) ];
}

=comment
 now @records looks like this:
 @records = (
    ['foo','gabba','12'],
    ['bar','hey','2'],
    ['baz','gabba','38']
 );
 the elements in []'s are array references

 now store the array references based on the order
 of the 3rd element, which is a number - numbers
 are compared with the <=> operator, strings are
 comparted with the cmp operator - $a and $b are
 magic variables that contain the two items being
 compared - if you want ascending order, compare
 $a to $b - for descencing order, compare $b to $a
=cut

my @sorted = sort { $b->[$item_no] <=> $a->[$item_no] } @records;

=comment
 that's it! now print out the results - the tricky part
 is that @sorted is a list of list REFERENCES, so we need
 to do some extra work to de-reference them
=cut

foreach my $line (@sorted) {
   print join(', ', @$line), "\n";
}

=comment
 the following would normally be found in a data file.
 i originally delimited these values with tabs, but they
 will probably turn into spaces when you copy and paste
 that's why i used /\s+/ instead of /\t/ in split above
=cut

__DATA__
foo     gabba     12
bar     hey       2
baz     gabba     38
[download]

Hope this helps, and don't forget to erase the comments when you are done ;)
jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
F--F--F--F--F--F--F--F--
(the triplet paradiddle)

UPDATE - changed multi-line comment style from # to POD

---

---

• 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> <u> <ul>

• 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 intervention).
• Want more info? How to link or How to display code and escape characters are good places to start.