How can I get sub-folder names in the working directory using perl? - perl

Question

I have a few sub-folders in the main folder. My program will do some calculations in each sub-folder. Firstly the code will create the "result" folder in main folder for all calculations. And, for the calculation in each sub-folder I want to create a folder in the "result" folder. But they should have the same name as sub-folder.
My working directory is "/home/abc/Desktop/test". The "test" is my main folder. There are "a", "b" and "c" sub-folders in "test" folder. My code creates the "result" folder in "test" main folder. But it also should create "a", "b" and "c" sub-folders in "result" folder. How can I fix my code?
#!/usr/bin/env perl
use strict;
use warnings;
use File::Path qw/make_path/;
use Cwd;
my $dir = cwd();
opendir (DIR, $dir) or die "Unable to open current directory! $!\n";
my #subdirs = readdir (DIR) or die "Unable to read directory! $!\n";
closedir DIR;
my $result_path = "$dir/results";
make_path("$result_path");
foreach my $subdir ( sort #subdirs ) {
chdir($subdir) or die "Cannot cd to $dir: $!\n";
make_path("$result_path/$subdir");
system("echo '1 0' | program -f data.mol -o $result_path/$subdir outfile.txt");
chdir("..");
}

Answer 1

I don't think File::Find::Rule is a good choice for this problem. The module's speciality is recursively searching directory trees, and here you just want a list of all the directories in a single folder. That can very simply be done with grep -d, glob '*'
Here's a version that uses the File::chdir module as per your previous question. It avoids the need for Cwd and File::Basename, and it allows you to localise the current working directory so that there is no need for chdir '..' at the end of each loop.
use strict;
use warnings;
use File::chdir;
my #folders = grep -d, glob '*';
my $result_path = "$CWD/result";
mkdir $result_path;
for my $folder ( #folders ) {
my $result_folder = "$result_path/$folder";
mkdir $result_folder;
local $CWD = $folder;
system("echo '1 0' | program -f data.mol -o $result_folder/output.txt");
}

Answer 2

File::Find::Rule->directory->in( $dir );
finds all directories recursively down the directory tree with starting point $dir. For each directory it finds, you are taking the basename.
So, when it comes across $dir/test/a, the basename of that is a, and your code goes ahead and creates result/a.
I suspect you do not need to find all the directories in a tree -- but given your jumbled problem description it is not easy to be certain.
Maybe you just want to opendir the directory, readdir all the entries keeping only directories other than . and .., and closedir when you are done instead of traversing the entire tree under $dir.