Dir Tree in Perl

[Hopfi]

Hello, Ive tried to make a directory listing in tree-style with PERL but failed.. In Batch its working fine but I cant figure out how I could do it in perl. Would be really nice if someone could tell me. Heres the batch-code if you dont know what i mean:

@echo off
 Set USB=%CD%
 CD C:\
 echo tree /a /f >%USB%\echotree.cmd
 %USB%\echotree.cmd >%USB%\results.txt
 exit

[Khen1950fx]

For something simple, try tree. For a cmdline example:

tree /var

[tobyink]

PerlMonks mangled my source code because it contained non-ASCII characters. So I've posted to github instead...

https://gist.github.com/4011150

[Hopfi]

ok got it done. i didnt use tree because im trying to avoid using cpan for this project. heres the code if someones interested:

#!/usr/bin/perl

($dir) = @ARGV;
open (MYFILE, '>>data.txt') || die;
&loopDir($dir, "");
exit;

sub loopDir {
    $dir = "." unless $dir;
    local($dir, $margin) = @_;
    chdir($dir) || die "Cannot chdir to $dir\n";
    local(*DIR);
    opendir(DIR, ".");
    while ($f=readdir(DIR)) {
        next if ($f eq "." || $f eq "..");
        print MYFILE "$margin$f\n";
        if (-d $f) {
            &loopDir($f,$margin."   ");
        }
    }
    closedir(DIR);
    chdir("..");
}
close (MYFILE);

[afoken]

im trying to avoid using cpan for this project

Bad idea. Your code is also sub-optimal:

• use strict missing
• & in front of function calls does not do what you think. Get rid of it, this ain't ancient Perl 4.
• local instead of my
• Recursion in loopDir will eventually run out of handles. Collect all subdirectories, then recurse after closing the directory handle. Or use a directory queue (shift the directory to read from, push every new directory found, run until queue is empty) and completely get rid of the recursion.
• close (MYFILE) is unreachable due to exit in front of it
• Two-argument open instead of three-argument open. Do you really need to support perl < 5.6 (more than twelve years old)?
• Bareword file handles instead of lexical ones
• open || die instead of open or die, same problem with chdir
• die without an error message ($!)
• opendir lacks an error check.

Alexander