Question

I’m trying to get the behavior like the “tree” command on linux or unix systems where the function returns a list or array of directories in its full path.

Example

~/
~/Pictures
~/Movies
~/Downloads
~/Documents
~/Documents/work
~/Documents/important
~/Documents/bills
~/Music
~/Music/80s/

etc …. etc…

Answer 1

foreach (new RecursiveIteratorIterator (new RecursiveDirectoryIterator ('.')) as $x)
{
        echo $x->getPathname (), "\n";
}

Update #1:

If you want empty directories to be listed as well, use RecursiveIteratorIterator::CHILD_FIRST

foreach (new RecursiveIteratorIterator (new RecursiveDirectoryIterator ('.'), RecursiveIteratorIterator::CHILD_FIRST) as $x)
{
    echo $x->getPathname (), "\n";
}