PHP Glob sub-folders with pattern

glob-sub-directories.php

<?php

/*
* reference: https://stackoverflow.com/a/54324543/5077529
*/

// This example allows 0-3 arbitrary subfolders:
glob("$root/{,*/,*/*/,*/*/*/}test_*.zip", GLOB_BRACE);

// Or for multiple file types(for example .pdf,.mp4 and .mp3):
glob("$root/{*.pdf,*/*.pdf,*/*/*.pdf,*/*/*/*.pdf,*.mp4,*/*.mp4,*/*/*.mp4,*/*/*/*.mp4,*.mp3,*/*.mp3,*/*/*.mp3,*/*/*/*.mp3}",  GLOB_BRACE)