PHP: file_exists

Opis

bool file_exists ( string nazwa_pliku )

Zwraca TRUE jeśli podany plik lub katalog w parametrze nazwa_pliku istnieje; FALSE w przeciwnym wypadku.

Pod Windows użyj //nazwa_komputera/udostepnione/nazwa_pliku lub \\nazwa_komputera\udostepnione\nazwa_pliku aby sprawdzić pliki udostępnione przez sieć.

Przykład 1. Sprawdzanie czy plik istnieje


<?php  

  $filename = '/sciezka/do/foo.txt';  

    

  if (file_exists($filename)) {  

      echo "Plik $filename istnieje";  

  } else {  

      echo "Plik $filename nie istnieje";  

  }  

  ?>

Notatka: Wyniki działania tej funkcji są buforowane. Zobacz opis funkcji clearstatcache() aby uzyskać więcej informacji.

Podpowiedź: Od wersji 5.0.0 PHP ta funkcja może być użyta także z niektórymi wrapperami URL. Zobacz Dodatek L aby uzyskać listę wrapperów które obsługują funkcjonalność z rodziny stat().

Patrz także is_readable(), is_writable(), is_file() i file().

User Contributed Notes


I wrote this little handy function to check if an image exists in a directory, and if so, return a filename which doesnt exists e.g. if you try 'flower.jpg' and it exists, then it tries 'flower[1].jpg' and if that one exists it tries 'flower[2].jpg' and so on. It works fine at my place. Ofcourse you can use it also for other filetypes than images.



<?php

function imageExists($image,$dir) {



    $i=1; $probeer=$image;



    while(file_exists($dir.$probeer)) {

        $punt=strrpos($image,".");

        if(substr($image,($punt-3),1)!==("[") && substr($image,($punt-1),1)!==("]")) {

            $probeer=substr($image,0,$punt)."[".$i."]".

            substr($image,($punt),strlen($image)-$punt);

        } else {

            $probeer=substr($image,0,($punt-3))."[".$i."]".

            substr($image,($punt),strlen($image)-$punt);

        }

        $i++;

    }

    return $probeer;

}

?>


here a function to check if a certain URL exist:

<?php

    function url_exists($url) {

        $a_url = parse_url($url);

        if (!isset($a_url['port'])) $a_url['port'] = 80;

        $errno = 0;

        $errstr = '';

        $timeout = 30;

        if(isset($a_url['host']) && $a_url['host']!=gethostbyname($a_url['host'])){

            $fid = fsockopen($a_url['host'], $a_url['port'], $errno, $errstr, $timeout);

            if (!$fid) return false;

            $page = isset($a_url['path'])  ?$a_url['path']:'';

            $page .= isset($a_url['query'])?'?'.$a_url['query']:'';

            fputs($fid, 'HEAD '.$page.' HTTP/1.0'."\r\n".'Host: '.$a_url['host']."\r\n\r\n");

            $head = fread($fid, 4096);

            fclose($fid);

            return preg_match('#^HTTP/.*\s+[200|302]+\s#i', $head);

        } else {

            return false;

        }

    }

?>



in my CMS, I am using it with those lines:

<?php

        if(!isset($this->f_exist[$image]['exist']))

            if(strtolower(substr($fimage,0,4)) == 'http' || strtolower(substr($fimage,0,4)) == 'www.'){

                if(strtolower(substr($image,0,4)) == 'www.'){

                    $fimage = 'http://'.$fimage;

                    $image = 'http://'.$image;

                }

                $this->f_exist[$image]['exist'] = $this->url_exists($fimage); //for now

            } else {

                $this->f_exist[$image]['exist'] = ($fimage!='' && file_exists($fimage) && is_file($fimage) && is_readable($fimage) && filesize($fimage)>0);

            }

        }

?>


The following script checks if there is a file with the same name and adds _n to the end of the file name, where n increases. if img.jpg is on the server, it tries with img_0.jpg, checks if it is on the server and tries with img_1.jpg.

<?php 

  $img = "images/".$_FILES['bilde']['name'];

  $t=0;

  while(file_exists($img)){

    $img = "images/".$_FILES['bilde']['name'];

    $img=substr($img,0,strpos($img,"."))."_$t".strstr($img,".");

    $t++;

  }

  move_uploaded_file($_FILES['bilde']['tmp_name'], $img);

?>


I recently had an issue with PLESK and copying file to other directories with the move_uploaded file function.



This would work on every linux server except plesk servers. I could figure it out and have yet to find out.  I had to create a work a round and decided to use the exec() function.



As noted above the file_exist() function must need to wait for some time and I found the looking function a waste of resouces and didn't work for me anyway. So this is what I came up with.



function cp($source,$destination){



$cmd="cp -u ".$source ." ".$destination; //create the command string to copy with the update option

exec($cmd); //exec command

$cmd_test="ls -la ".$destination; //list file 

exec($cmd_test,$out); 

//If the file is present it $out[0] key will contain the file info. 

//if it is not present it will be null

if (isset($out[0])){

     return true; 

}else{

     return false;

}

    }


Also while using the file_exists file, please make sure you do not start using stuff like,



<?php



if(file_exists($_GET['file'] . '.php')) {

    include($_GET['file'] . '.php';

}



?>



you could use something like this..



<?php

    $inrep = "./";

    $extfichier = ".php";

    $page = $inrep.basename(strval($_REQUEST["page"]),$extfichier).extfichier;

    if(file_exist($page)) {

        include($page);

    }

?>



or even hardcode it.



  So since pretty much all commercial server(s) have url_fopen on.. you can imagine that file_exists($_GET['file']. '.php') 

is rather .. unsecure :)



-David Coallier


If checking for a file newly created by an external program in Windows then file_exists() does not recognize it immediately.  Iy seems that a short timeout may be required.



<?

    $file = 'file.tmp';

    if ($h = popen("start \"bla\" touch $file", "r")) {

      pclose($h);

   // now I would like know if a file was created

   // note: usleep not supported 

      $start = gettimeofday();   

      while (!file_exists(trim($file, " '\""))) {

        $stop = gettimeofday();

        if ( 1000000 * ($stop['sec'] - $start['sec']) + $stop['usec'] - $start['usec'] > 500000) break;  // wait a moment

     }



     if (file_exists($file))   // now should be reliable

?>


That is true feshi. But, if you have your server configured correctly, those access logs will only be accessible by an admin or the root account. The webuser account that runs the php script will be unable to start reading from that file. That's the easiest fix.


this code looks inocent



<?php

$filename=$_REQUEST["var"];

$filename .= ".data";

file_exist($filename){

  include($filename);

}

?>



but if you pass something like script.php?var=test%00asbs

it should really can do bad things like including accesslog files if you replace "test" with something like "../logs/accesslog"


concerning file_exists and safe_mode:

if safe_mode=ON and $file (in safe_mode_include_dir) is not owned by the user who executes file_exists($file), file_exists returns FALSE but still $file can be included;

I could handle this by setting safe_mode_gid=On and appropriate group-ownership


Nathaniel, you should read the manual carefuly next time prior to posting anything here, as all you indicated is the fact you missed the idea of the include_path. To remind - include_path is for some functions only, mainly intended for include and require to simpify include/require operations (kinda way the #include works). It is NOT for any filesystem function, which would be damn annoying than helpful, which is quite understandable and obvious.


file_exists will have trouble finding your file if the file permissions are not read enabled for 'other' when not owned by your php user. I thought I was having trouble with a directory name having a space in it (/users/andrew/Pictures/iPhoto Library/AlbumData.xml) but the reality was that there weren't read permissions on Pictures, iPhoto Library or AlbumData.xml. Once I fixed that, file_exists worked.


I spent the last two hours wondering what was wrong with my if statement: file_exists($file) was returning false, however I could call include($file) with no problem.



It turns out that I didn't realize that the php include_path value I had set in the .htaccess file didn't carry over to file_exists, is_file, etc.



Thus:



<?PHP

// .htaccess php_value include_path '/home/user/public_html/';



// includes lies in /home/user/public_html/includes/



//doesn't work, file_exists returns false

if ( file_exists('includes/config.php') )

{

     include('includes/config.php');

}



//does work, file_exists returns true

if ( file_exists('/home/user/public_html/includes/config.php') )

{

    include('includes/config.php');

}

?>



Just goes to show that "shortcuts for simplicity" like setting the include_path in .htaccess can just cause more grief in the long run.


On nix systems file_exists will report a link that doesn't point to a valid file as non-existant, ie: the link itself exists but the file it points to does not.  Using is_link will report true whether the link points to a valid file or not.