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Re: [Omaha.pm] Fwd: Perl and recursion...

I'd agree with Theodore's comments...without refering back to documentation, I'm pretty sure you're hitting a scoping issue on your DIR file handle.
As an alternative to frontloading all the filenames into an array, have you looked at the File::Find module? It confused the heck out of me when I first looked at it, but once you figure it out, it can do all sorts of neat stuff with directory trees and their content. 

Richard
On Tue, 15 Nov 2005 16:20:40 -0600, Theodore Katseres <tedkat@gmail.com> wrote: 


---------- Forwarded message ----------
From: Theodore Katseres <tedkat@gmail.com>
Date: Nov 15, 2005 2:54 PM
Subject: Re: [Omaha.pm] Perl and recursion...
To: dan@linder.org


Sorry, Your code was right!
The problem seems to be with while test. It keeps DIR descriptor open
thru the recursion. I think this is why it dives and then quits.

By loading up your files and directories into memory before recursion
you no longer depend on the File descriptor to keep its previous
state.

    opendir( DIR, $dir ) or die $!;
    my @arr = grep { !/^\.+$/ } readdir(DIR); ## just ignore . and ..
    close(DIR);

    while .....

On 11/15/05, Daniel Linder <dan@linder.org> wrote:

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
 On Tue, November 15, 2005 13:31, Theodore Katseres wrote:
 > It appears that no recursion is happening passed the initial dive. {
 > ProcFiles("/tmp") }

 I agree -- when I take out the '&ProcFiles("$dir/$file");' line, it
continues through the /tmp directory fine.  With the recursive call to
itself, I can watch the script dive into the sub-directory (/tmp/dir1), and it processes all the files in /tmp/dir1, but when it finishes with the files in "dir1" the program quits. Unless I am missing something, I thought it should go back one level to the initial invocation of ProcFiles and continue 
where it left off there...

 > Check my comments.
 >
 > <Snip && Replace>
 > #!/bin/perl -w
 > use strict;
 >
 > sub ProcFiles {
 > my $dir = shift;
 >
 > opendir( DIR, $dir ) or die $!;
 >
 > while ( my $file = readdir(DIR) ) {
 >
 > next if ( -d "$dir/$file" && $file =~ /^\./ );
 >
 > # above makes sure this block of code never gets executed
The line you mention ("next if ...") is used to make sure I skip the "." and ".." entries in the subdirectory -- otherwise it would back out of the "/tmp" to "/" and work there! :( (It also has the effect of ignoring files 
with a leading "." -- that's also by design.)

 > if ( -d "$dir/$file" ) {
 >
 > printf( "Diving into\"%s/%s\".\n", $dir, $file );
 >
 > &ProcFiles("$dir/$file");
 >
 > next;
 >
 > }
 >
 > # your printing files that don't begin with "."
True -- in my real script, this print line is replaced with a small bit of code to do some real work! In the example I posted to OLUG I wanted to keep 
it simple and see if I could make it work...

 > printf( "Adding\"%s/%s\".\n", $dir, $file );
 >
 > }
 >
 > closedir(DIR);
 >
 > }
 >
 > &ProcFiles("/tmp");

 Ted, thanks for your input.

 Dan

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--
Ted Katseres
      ||=O=||


--
Ted Katseres
      ||=O=||
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