Re: Hi Monks could you pls help Perl dummy user

[Anonymous Monk]

recursion doesn't work i don't know why?

Because your read_dir is not safe to use for recursion - $dir and all the other variables in the sub are global. You need to use lexical variables, for example my $dh instead of DH, to make them local to the blocks they are defined in. Using warnings and strict (use warnings; use strict;) will help you with this and many other potential problems.

without fancy module

Why? File::Find is in the core.

use File::Find;
find( sub {
    return unless -r && -f;
    my $size = -s;
    print "$File::Find::name $size\n" if $size > 51200; 
  }, $path );

[LanX]

> Using warnings and strict (use warnings; use strict;) will help you with this and many other potential problems.

unfortunately do neither use strict nor use warnings complain about bareword filehandles, and nowadays I wonder why.

They don't have an explicit package name and localizing with a glob local *FH isn't trivial.

[sibyurik]

That's output for my program that doesn't go into any directories. Do you know why?

yura@yura:~$ ls -a
.                   .bashrc  dir_tree          .face                  
+.goutputstream-51G14W  .ICEauthority     .mixxx    Pictures       .pu
+lse-cookie  Templates         .xsession-errors.old
..                  .cache   .dmrc             .gconf                 
+.goutputstream-F8CZ4W  .java             Mixxx     .profile       .Sk
+ype         Videos
.adobe              .compiz  Documents         .gnome2                
+.goutputstream-TBVW4W  java_progs        module    project        .ss
+h           .viminfo
.apport-ignore.xml  .config  Downloads         .gnome2_private        
+.goutputstream-Z89K4W  .local            .mozilla  project_final  .sw
+t           workspace
.bash_history       .dbus    .eclipse          .goutputstream-11KV4W  
+.gstreamer-0.10        .macromedia       Music     Public         sys
+err.log     .Xauthority
.bash_logout        Desktop  examples.desktop  .goutputstream-1UX14W  
+.gtk-bookmarks         .mission-control  perl      .pulse         sys
+out.log     .xsession-errors
yura@yura:~$ perl dir_tree 
.ICEauthority 33170
module 433
project_final 4515
dir_tree 704
.profile 675
project 4486
sysout.log 19807
examples.desktop 8445
syserr.log 2350
.pulse-cookie 256
.xsession-errors.old 828
.viminfo 14093
.bash_history 17965
.face 9447
.bashrc 3637
.bash_logout 220
yura@yura:~$

[sibyurik]

I used strict and warnings but it doesn't go into any other directories other than current. Thus recursion doesn't work correctly i guess. Could you pls help me tofix it now?

#!/usr/bin/perl

#
#Author: Yury Sibirski
#Name: users_home_dir
#Date: 16 December 2014
#Purpose: This program analyze the directory structure of a Linux disk
+ and identify any files larger than 500 kbytes
#
use strict;
use warnings;
my $path = shift || '.';

read_dir($path);

sub read_dir
{
        my $dir = shift;
        opendir (my $DH, $dir) or die "Couldn't open current directory
+: $!";
        while (my $file = readdir($DH))
        {#print "$file\n";
                if ($file eq "." or $file eq "..")
                {
                        next;
                }
                elsif (-z $file)
                {
                        next;
                }
                elsif (-r $file and -f $file)
                {
                        my $size = -s $file;
                        print $file," ",$size, "\n" if $size > 200;
                }

                elsif (-d $file)
                {
                        read_dir($file);
                }
        }
closedir $DH;
}

[LanX]

works for me!

[sibyurik]

It checks all your directories and prints files that bigger than 200?

[jellisii2]

This 1000 times. Beginners guide to File::Find has a nice simple explanation on how to use it. The code that you have written and commented out is potentially dangerous as it will blindly follow symlinks. Since you're on Linux, this is a very real concern.

[sibyurik]

It gives me an error like no &wanted subroutine given at /usr/share/perl/5.18/File/Find.pm line 1073. NO IDEA WHY?

#!/usr/bin/perl
use File::Find;
use strict;
use warnings;
my $path = shift || '.';
find($path);

find( sub {
    return unless -r && -f;
    my $size = -s;
    print "$File::Find::name $size\n" if $size > 51200;
  }, $path )