{"id":443,"date":"2005-12-22T00:07:35","date_gmt":"2005-12-21T22:07:35","guid":{"rendered":"http:\/\/frenchfragfactory.net\/ozh\/archives\/2005\/12\/22\/php-non-recursive-function-through-directories\/"},"modified":"2007-05-08T16:01:46","modified_gmt":"2007-05-08T14:01:46","slug":"php-non-recursive-function-through-directories","status":"publish","type":"post","link":"https:\/\/planetozh.com\/blog\/2005\/12\/php-non-recursive-function-through-directories\/","title":{"rendered":"PHP Non Recursive Function Through Directories"},"content":{"rendered":"

I needed a recursive function to go through directories and subdirectories, so I headed to PHP.net's readdir()<\/a> page, knowing that I would find one in user comments. Or did I need a recursive function ? Hell no. I've found the nifty neat following function, which does not recursively calls itself. And what's so cool about it, you may ask ? Speed.<\/p>\n

\n\n\t\t
\n\n\t\t
\n\t\t\t\t\t\t< View plain text<\/span> ><\/a>\n\t\t\t\t\t<\/div>\n\n\t\t
php<\/div>\n\n\t\t\n\t\t
\n\n\t<\/div>\n\t\n\t
\n\t\t
  1. <?php<\/span><\/div><\/li>\n
  2. function<\/span> list_directory(<\/span>$dir<\/span>)<\/span> {<\/span><\/div><\/li>\n
  3.    $file_list<\/span> =<\/span> ''<\/span>;<\/span><\/div><\/li>\n
  4.    $stack<\/span>&<\/span>#91;&#93; = $dir;<\/span><\/div><\/li>\n
  5.   while<\/span> (<\/span>$stack<\/span>)<\/span> {<\/span><\/div><\/li>\n
  6.       $current_dir<\/span> =<\/span> array_pop<\/span>(<\/span>$stack<\/span>)<\/span>;<\/span><\/div><\/li>\n
  7.       if<\/span> (<\/span>$dh<\/span> =<\/span> opendir<\/span>(<\/span>$current_dir<\/span>)<\/span>)<\/span> {<\/span><\/div><\/li>\n
  8.          while<\/span> (<\/span>(<\/span>$file<\/span> =<\/span> readdir<\/span>(<\/span>$dh<\/span>)<\/span>)<\/span> !==<\/span> false<\/span>)<\/span> {<\/span><\/div><\/li>\n
  9.             if<\/span> (<\/span>$file<\/span> !==<\/span> '.'<\/span> AND $file<\/span> !==<\/span> '..'<\/span>)<\/span> {<\/span><\/div><\/li>\n
  10.                $current_file<\/span> =<\/span> "{$current_dir}<\/span>\/{$file}<\/span>"<\/span>;<\/span><\/div><\/li>\n
  11.                if<\/span> (<\/span>is_file<\/span>(<\/span>$current_file<\/span>)<\/span>)<\/span> {<\/span><\/div><\/li>\n
  12.                   $file_list<\/span>&<\/span>#91;&#93; = "{$current_dir}\/{$file}";<\/span><\/div><\/li>\n
  13.               }<\/span> elseif<\/span> (<\/span>is_dir<\/span>(<\/span>$current_file<\/span>)<\/span>)<\/span> {<\/span><\/div><\/li>\n
  14.                   $stack<\/span>&<\/span>#91;&#93; = $current_file;<\/span><\/div><\/li>\n
  15.               }<\/span><\/div><\/li>\n
  16.             }<\/span><\/div><\/li>\n
  17.          }<\/span><\/div><\/li>\n
  18.       }<\/span><\/div><\/li>\n
  19.    }<\/span><\/div><\/li>\n
  20.    return<\/span> $file_list<\/span>;<\/span><\/div><\/li>\n
  21. }<\/span><\/div><\/li>\n
  22. ?><\/span><\/div><\/li>\n<\/ol>\t<\/div>\n\n<\/div>\n\n

    The function returns an array of files from directory passed as argument and subdirectories. The user who submitted this function added a few benchmarks against an average recursive function, to find out that this one is about 50% quicker.<\/p>\n

    Just as anybody I guess, I've been using various recursive functions for years now, and I just had never thought about why or how to do it differently. Damn. So many CPU cycles wasted for nothing :)<\/p>\n","protected":false},"excerpt":{"rendered":"

    Best way to go through (sub)directories<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[2,10],"class_list":["post-443","post","type-post","status-publish","format-standard","hentry","tag-code","tag-php"],"_links":{"self":[{"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/posts\/443","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/comments?post=443"}],"version-history":[{"count":0,"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/posts\/443\/revisions"}],"wp:attachment":[{"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/media?parent=443"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/categories?post=443"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/planetozh.com\/blog\/wp-json\/wp\/v2\/tags?post=443"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}