While writing a script to scan folder paths for certain file type, I had a problem. Maybe I will write the script first: 
use File::Find;
open(INLIST, $ARGV[0]) or die "cannot open $ARGV[0]: $!\n";
my @all_paths = <INLIST>;
close INLIST;
chomp @all_paths;

foreach my $path(@all_paths) {
     if (-f $path && $path=~/\.dirlist$/){
         open (LIST, $path) or do { print "cannot open $path: $!\n"; n
+ext; };
         my @temp = <LIST>;
         chomp @temp;
         push @all_paths, @temp;
         close LIST;
         next;
     } elsif (-d $path) {
         find(\&scan_path_n_rename_file, $path);
     }
}

[download]
THe actually reads a file that has list of paths, scans each path & renames files that has certain extension to .bak
The list file can contain a path to another link file...
so i used to check this condition in my foreach & push the links from @temp to @all_paths.

This worked... I want to know why and how this works???
How is it possible to modify a variable that is already being used (ex: @all_paths used in foreach)
Why can i still use the updated variable (@all_paths gets updated by push & the script scans those paths also...)

Thanks

MY Perl BLog: http://techdiary-viki.blogspot.com

In reply to How & why does this work? by Viki@Stag

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