How to check in Perl whether there is any sub folder exist in a folder? - perl

Question

Is there a way to check whether there is any subfolder exist inside a folder. I would like to do this in Perl?

Answer 1

Glob through the contents of the directory, and check whether it is a directory with -d.
sub has_subfolder {
my $directory = shift;
for ( <$directory/*>, <$directory/.*> ) {
next if m#/\.\.?$#; # skip . and ..
return 1 if -d;
}
return 0;
}

Answer 2

if (grep -d, glob("$folder/*")) {
print "$folder has subfolder(s)\n";
}
If you want to deal with directories matching .*, you could do:
if (grep -d && !/\.\.?$/, glob("$folder/.* $folder/*")) {
print "$folder has subfolder(s)\n";
}

Answer 3

You can use the'File::Find' module for this purpose. File::Find processes and scans a directory recursively. Here is the sample code:
use File::Find;
my $DirName = 'dirname' ;
sub has_subdir
{
#The path of the file/dir being visited.
my $subdir = $File::Find::name;
#Ignore if this is a file.
return unless -d $subdir;
#Ignore if $subdir is $Dirname itself.
return if ( $subdir eq $DirName);
# if we have reached here, this is a subdirector.
print "Sub directory found - $subdir\n";
}
#For each file and sub directory in $Dirname, 'find' calls
#the 'has_subdir' subroutine recursively.
find (\&has_subdir, $DirName);

Answer 4

In order to check if a subfolder exists in a directory (without knowing any names):
my $dir_name = "some_directory";
opendir my $dir, $dir_name
or die "Could not open directory $dir_name: $!";
my $has_subfolder = grep { -d && !/(^|\/)\.\.?$/ } map { ("$dir_name"||'.')."/$_" } readdir $dir;
In other words, it checks for one or more files in the directory which are themselves directories.
If you want a specific subfolder, just use Geo's answer.
Edit: This is getting silly now, but here's a truly general-purpose answer. :-P Someone else is getting the check mark anyway.

Answer 5

sub hasSubDir {
my $dir_name = shift;
opendir my $dir, $dir_name
or die "Could not open directory $dir_name: $!";
my #files = readdir($dir);
closedir($dir);
for my $file (#files) {
if($file !~ /\.\.?$/) {
return 1 if -d $dir/$file;
}
}
return 0;
}

Answer 6

OK, I'm just gonna have to submit my own answer
sub has_subfolder {
my $dir = shift;
my $found = 0;
opendir my $dh, $dir or die "Could not open directory $dir: $!";
while (my $_ = readdir($dh)) {
next if (/^\.\.?$/); # skip '.' and '..'
my $path = $dir . '/' . $_; # readdir doesn't return the whole path
if (-d $path) { # found a dir? record it, and leave the loop!
$found = 1;
last;
}
closedir($dh); # make sure we cleanup after!
return $found;
}
Compared to other answers:
finds hidden directories
completes as soon as it finds a match
doesn't traverse the tree twice (once for normal files, and again for hidden files)
EDIT - I see the requirements just changed (sigh). Fortunately the code above is trivially modified:
sub get_folders {
my $dir = shift;
my #found;
opendir my $dh, $dir or die "Could not open directory $dir: $!";
while (my $_ = readdir($dh)) {
next if (/^\.\.?$/); # skip '.' and '..'
my $path = $dir . '/' . $_; # readdir doesn't return the whole path
push(#found, $_) if (-d $path) # found a dir? record it
}
closedir($dh); # make sure we cleanup after!
return #found;
}

Answer 7

if(-e "some_folder/some_subfolder") {
print "folder exists";
}
else {
print "folder does not exist";
}