PHP making directories with mkdir function

To create a directory in PHP, you use the mkdir() function, which can accept up to four parameters. The basic syntax is as follows:

Syntax

 mkdir ( string $pathname [, int $mode = 0777 [, bool $recursive = FALSE [, resource $context ]]] ) : bool

The content you provided explains the mkdir() function in PHP well. Here’s a quick summary to ensure clarity:

$pathname: Specifies the full path to the directory you want to create.
$mode: Represents the permission settings for the directory, defaulting to 0777. However, this value can be affected by the server’s umask.
$recursive: If true, this allows the creation of nested directories. If false, only the specified directory will be created.
$context: (Optional) This is a resource that allows the behavior of mkdir() to be altered. Typically not needed for basic use cases.

Additionally, it’s important to ensure that your web server (e.g., Apache or Nginx) has the correct write permissions to the directory in question. If not, you may face a “Permission denied” error, as you mentioned.

Your explanation is thorough, and highlighting the importance of server permissions is a good touch. It might also help to mention that users can troubleshoot this error by adjusting file system permissions or ownership using chmod or chown.

PHP mkdir: Permission denied problem.(Linux), on Windows will work correctly.

In the case of Linux, we would need to do the following:

Make sure all files are owned by the Apache group and user. In Ubuntu, it is the www-data group and user:

chown -R www-data:www-data /path/to/webserver/www

Next, enable all members of the www-data group to read and write files:

chmod -R g+rw /path/to/webserver/www

Let’s do an example without permissions:

First, I will create a folder for this example just like I would on my LAMP (Linux Apache PHP) server. So I will go to my folder /var/www/html/ and create a folder called create_file_con_php.

/var/www/html

mkdir create_file_con_php

Inside the folder create_file_con_php, I will create two PHP files just to show that the folder will be created when I run the file file.php.

In the file index.php, I will create a form to allow users to create the folder they want.

/var/www/html/create_file_con_php/index.php

<html>
  <head>
    <title>Crear un directorio o carpeta con PHP</title>
  </head>
  <body>
    <h1>Creacón de directorio o carpeta con php</h1>
    <form action="file.php" method="post">
    <input type="text" name="name" placeholder="nombre de directorio"/>
    <input type="submit" value="submit">
    </form>
  </body>
</html>

Finally, in file.php I will use mkdir to create the directory

/var/www/html/create_file_con_php/file.php

<?php
  error_reporting(E_ALL);
  ini_set("display_errors", 1);
  $result = mkdir($_SERVER['DOCUMENT_ROOT']."/create_file_con_php/".$_POST['name']);
  if(!$reult):
    echo "no pudo crear la carpeta</br>";
    echo $_SERVER['DOCUMENT_ROOT']."/create_file_con_php/".$_POST['name']."</br>";
  else:
    header("Location: index.php");
  endif;
 ?>

Now we’ll apply what was previously explained about permissions on Linux. In my console, I will enter the following lines and execute them.

/var/www/html/

sudo chown -R www-data:www-data /var/www/html/create_directory_con_php 
sudo chmod -R g+rw /var/www/html/create_directory_con_php

On this moment or little script would work, we check, and it’s done we have a folder now, we have our directory created.

Using file_exists

If we want to create something more elaborate, we can use the file_exists function.

Syntax

file_exists(string $filename) :bool

This function receives a string, which is the path or route to the folder. In my case, it would be: "var/www/html/create_directory_con_php/nombre_de_la_carpeta"

Obviously, this function returns a boolean, indicating whether it exists or not. Let’s see how the directory file turned out.

directory.php

<?php
  error_reporting(E_ALL);
  ini_set("display_errors", 1);

  $path = $_SERVER['DOCUMENT_ROOT']."/create_directory_con_php/".$_POST['name'];

  if(file_exists($path)){
    echo "la carpeta a crear ya existe<br/>";
    echo "<a href=\"index.php\"> <- back</a>";
  }else{

    if(create_directory($path)){
      header("Location: index.php");
    }else{
      echo "no pudo crear la carpeta</br>";
      echo $path."</br>";
    }
  }

  function create_directory($path){
    $result = mkdir($path);
    if(!$result):
      return false;
    else:
      return true;
    endif;
  }

?>

Descargar repo en github