Unable to get absolute path of a file from $File::Find::name - perl - perl

Question

I am unable to get the absolute path of a file from $File::Find::name. It is showing undef vale as a output. Not able to figure it out why :( can any one please help me out in this
Error displayed is : Use of uninitialized value $file_name in concatenation
My Code :
use strict;
use warnings;
use File::Find;
use File::Path qw(make_path);
use File::Copy;
use Cwd;
use Data::Printer;
my $rootPATH = $ARGV[0];
my $id = $ARGV[1];
my #Arraypath;
my $file_name;
our $anr_name;
opendir( my $DIR, $rootPATH );
while ( my $entry = readdir $DIR ) {
next unless -d $rootPATH . '/' . $entry;
next if $entry eq '.' or $entry eq '..';
#print "Found directory $entry\n";
push( #Arraypath, ( split( "\n", $entry ) ) );
}
closedir $DIR;
my $count = 0;
foreach my $line (#Arraypath) {
my $fulllogpath = $rootPATH . "\\" . $line;
#print "$fulllogpath\n";
$count++;
start($fulllogpath);
}
sub start {
my $fulllogpath = shift;
our #content;
#print "$fulllogpath\n\n";
find( \&wanted, $fulllogpath );
sub wanted {
push #content, $_;
return;
}
foreach my $file (#content) {
# print "$file\n\n";
if ( $file =~ /traces[_d]*/ ) {
print "$file\n\n";
$file_name = $File::Find::name;
p $file_name;
print "$file_name\n";
}
}
}

Answer 1

Your program is very poorly layed out. It will be much simpler to write and debug code if you indent it properly and use carefully-chosen identifiers: a name like start for a subroutine is useless.
You also have unnecessary subroutine declarations which break up the program flow and make it awkward to follow.
Why do you have a couple of package variables (declared with our)? There is generally no need for them, and it is best to use lexical variables throughout, declared at an appropriate place so that all code has access to them if it needs it.
It is also preferable to use File::Spec to work with file paths, rather than manipulate them using string operators, with which it is easy to make a mistake.
The best way to manage the results of find is to work with absolute paths all the way through. It looks like you want to do more than just print the results returned by find since you load modules like Cwd and File::Copy, but without knowing what that further purpose is I cannot help you to write it.
This code removes all the subroutines and makes everything much more concise.
use strict;
use warnings;
use autodie;
use File::Find 'find';
use File::Spec;
use Data::Printer;
my ($root_path, $id) = #ARGV;
opendir my ($dh), $root_path;
my #dir_list =
grep -d,
map File::Spec->catfile($root_path, $_),
grep { not /\A\.\.?\z/ } readdir $dh;
closedir $dh;
my $count;
for my $dir (#dir_list) {
++$count;
find(sub {
return unless /traces[_d]*/;
my $file = $_;
print "$file\n\n";
my $file_name = $File::Find::name;
p $file_name;
print "$file_name\n";
}, $dir);
}

Answer 2

As has already been stated, $File::Find::name is valid only within the wanted function. Not outside of it.
However, I would recommend making the shift to using Path::Class and Path::Class::Rule for some simpler processing of your files in a cross platform compatible way:
use strict;
use warnings;
use Data::Printer;
use Path::Class;
use Path::Class::Rule;
my ( $root_path, $id ) = #ARGV;
my $dir = dir($root_path);
my $next = Path::Class::Rule->new->file->name(qr{traces[_d]*})->iter(
grep { $_->is_dir() } $dir->children
);
while ( my $file = $next->() ) {
# Accomplishes the same as your script. I suspect these prints statements are mostly for debugging though.
print $file->basename(), "\n\n";
p "$file";
print "$file\n";
}