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chown> <chgrp
Last updated: Mon, 26 Nov 2007

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chmod

(PHP 4, PHP 5)

chmod — 改变文件模式

说明

bool chmod ( string $filename , int $mode )

尝试将 filename 所指定文件的模式改成 mode 所给定的。

注意 mode 不会被自动当成八进制数值，而且也不能用字符串（例如 "g+w"）。要确保正确操作，需要给 mode 前面加上 0：

<?php
chmod("/somedir/somefile", 755);   // 十进制数，可能不对
chmod("/somedir/somefile", "u+rwx,go+rx"); // 字符串，不对
chmod("/somedir/somefile", 0755);  // 八进制数，正确的 mode 值
?>

mode 参数包含三个八进制数按顺序分别指定了所有者、所有者所在的组以及所有人的访问限制。每一部分都可以通过加入所需的权限来计算出所要的权限。数字 1 表示使文件可执行，数字 2 表示使文件可写，数字 4 表示使文件可读。加入这些数字来制定所需要的权限。有关 UNIX 系统的文件权限可以阅读手册“man 1 chmod”和“man 2 chmod”。

<?php
// Read and write for owner, nothing for everybody else
chmod("/somedir/somefile", 0600);

// Read and write for owner, read for everybody else
chmod("/somedir/somefile", 0644);

// Everything for owner, read and execute for others
chmod("/somedir/somefile", 0755);

// Everything for owner, read and execute for owner's group
chmod("/somedir/somefile", 0750);
?>

如果成功则返回 TRUE，失败则返回 FALSE。

Note: 当前用户指的是执行 PHP 的用户。很可能和通常的 shell 或者 FTP 用户不是同一个。在大多数系统下文件模式只能被文件所有者的用户改变。

Note: 本函数不能作用于远程文件，被检查的文件必须通过服务器的文件系统访问。

Note: 当安全模式打开的时候，PHP 会检查所操作的文件是否和正在执行的脚本具有相同的 UID （所有者）。要注意的是，不能修改 SUID，SGID 和 sticky bits。

参见 chown() 和 chgrp()。



chown> <chgrp
Last updated: Mon, 26 Nov 2007
 
add a note add a note User Contributed Notes
chmod
imurnane at internode dot on dot net
22-Jun-2008 02:52
Just stumbled accross this, to create a 777 directory..
mkdir ("test", 0410);
chmod ("test", 0777);

The created folder is 777 insted of 755!
paul maybe at squirrel mail org
24-Apr-2008 08:09
Note that info at rvgate dot nl's chmodnum function produces INCORRECT results.  The resutls are base-10 numbers that only LOOK like they are octal numbers.  The function also ignores setuid, setgid and sticky bits, and will produce incorrect numbers if such a file is encountered.  Instead, this brute-force code works.  Maybe there is something more slick, but this isn't too CPU-intensive (note that it assumes you've error-checked that you indeed have a 10-character string!):

      $permissions = 'drwxr-xr-x';  // or whatever
      $mode = 0;

      if ($permissions[1] == 'r') $mode += 0400;
      if ($permissions[2] == 'w') $mode += 0200;
      if ($permissions[3] == 'x') $mode += 0100;
      else if ($permissions[3] == 's') $mode += 04100;
      else if ($permissions[3] == 'S') $mode += 04000;

      if ($permissions[4] == 'r') $mode += 040;
      if ($permissions[5] == 'w') $mode += 020;
      if ($permissions[6] == 'x') $mode += 010;
      else if ($permissions[6] == 's') $mode += 02010;
      else if ($permissions[6] == 'S') $mode += 02000;

      if ($permissions[7] == 'r') $mode += 04;
      if ($permissions[8] == 'w') $mode += 02;
      if ($permissions[9] == 'x') $mode += 01;
      else if ($permissions[9] == 't') $mode += 01001;
      else if ($permissions[9] == 'T') $mode += 01000;

      printf('Mode is %d decimal and %o octal', $mode, $mode);
zual__ at gogo dot mn
31-Oct-2007 08:53
greate ftp newfolder=dir;
chmod --dir change 777;

<?php
$ftp_server='server';
$conn_id = ftp_connect("$ftp_server");
ftp_login($conn_id, user, password);
ftp_mkdir($conn_id, dir/dir);
ftp_site($conn_id, 'CHMOD 777, dir/dir');
ftp_close($conn_id);
?>
til_roque at yahoo dot com
11-Oct-2007 11:03
Problem:
you are trying to circumvent SAFE_MODE setting that prevents you from using chmod() on files you uploaded via a regular ftp client, because php may run as user 'nobody', which is not the user from your ftp session.
using ini_set() won't work
using ftp_chmod() won't work either

Solution:
copy file to some temorary directory.
delete original file altogether.
copy temporary file back to original location.
do the chmod()
mmj048 at gmail dot com
05-Oct-2007 11:56
If you want to use a string for the second parameter, including user input, you MUST use octdec.

http://www.php.net/octdec
martin at aarhof dot eu
17-Aug-2007 10:15
Just for those peoples can't remeber the codes 777 and so on I just created a small class :-)

<?php

class Chmod
{
   
    private $dir;
    private $modes = array('owner' => 0 , 'group' => 0 , 'public' => 0);
   
    public function setOwnermodes($read,$write,$execute) {
        $this->modes['owner'] = $this->setMode($read,$write,$execute);
    }
   
    public function setGroupmodes($read,$write,$execute) {
        $this->modes['group'] = $this->setMode($read,$write,$execute);
    }

    public function setPublicmodes($read,$write,$execute) {
        $this->modes['public'] = $this->setMode($read,$write,$execute);
    }
   
    public function getMode() {
        return 0 . $this->modes['owner'] . $this->modes['group'] . $this->modes['public'];
    }
   
    private function setMode($r,$w,$e) {
        $mode = 0;
        if($r) $mode+=4;
        if($w) $mode+=2;
        if($e) $mode+=1;
        return $mode;
    }

   
}

$test = new Chmod;
$test->setOwnermodes(true,true,true);
$test->setGroupmodes(true,true,true);
$test->setPublicmodes(true,true,true);
chmod($dir , $test->getMode());
// chmods $dir to 0777
?>
Ambriel_Angel at www dot ambriels dot net/entry
25-Mar-2007 10:00
<?php
error_reporting(E_ERROR | E_PARSE);
/* Makes is so Directories are not browseable to the public,
removing only the Public = Read permission, while leaving
the other chmod permissions for the file in tact.

If you have exectue already on, and read off, public viewers will only
be able to view files through links, but not browse
around to see what's inside of directories and see what
you've got laying around. */
//-------------------------------------------------------
// Get file mode
// Get file permissions supported by chmod
function getmod($filename) {
   $val = 0;
   $perms = fileperms($filename);
   // Owner; User
   $val += (($perms & 0x0100) ? 0x0100 : 0x0000); //Read
   $val += (($perms & 0x0080) ? 0x0080 : 0x0000); //Write
   $val += (($perms & 0x0040) ? 0x0040 : 0x0000); //Execute
 
   // Group
   $val += (($perms & 0x0020) ? 0x0020 : 0x0000); //Read
   $val += (($perms & 0x0010) ? 0x0010 : 0x0000); //Write
   $val += (($perms & 0x0008) ? 0x0008 : 0x0000); //Execute
 
   // Global; World
   $val += (($perms & 0x0004) ? 0x0004 : 0x0000); //Read
   $val += (($perms & 0x0002) ? 0x0002 : 0x0000); //Write
   $val += (($perms & 0x0001) ? 0x0001 : 0x0000); //Execute

   // Misc
   $val += (($perms & 0x40000) ? 0x40000 : 0x0000); //temporary file (01000000)
   $val += (($perms & 0x80000) ? 0x80000 : 0x0000); //compressed file (02000000)
   $val += (($perms & 0x100000) ? 0x100000 : 0x0000); //sparse file (04000000)
   $val += (($perms & 0x0800) ? 0x0800 : 0x0000); //Hidden file (setuid bit) (04000)
   $val += (($perms & 0x0400) ? 0x0400 : 0x0000); //System file (setgid bit) (02000)
   $val += (($perms & 0x0200) ? 0x0200 : 0x0000); //Archive bit (sticky bit) (01000)

   return $val;
}

//-------------------------------------------------------
// Find out if file has mode
function hasmod($perms, $permission) {

# User Read = 0400 (256), Write = 0200 (128), Execute = 0100 (64)
# Group Read = 0040 (32), Write = 0020 (16), Execute = 0010 (8)
# Public Read = 0004 (4), Write = 0002 (2), Execute = 0001 (1)

    return (($perms & $permission) == $permission);
}

//-------------------------------------------------------
// Take the read option off of all the subdirectories of the included path
function pathlock($dir, $listall = false, $testrun = true) {
   echo "START @ " . date("F j, Y, h:i:s A") . "<br><br>";
   echo ($testrun ? '**Test Run Activated (no changes will be made).**<br><br>' : '**Live Run Activated.**<br><br>');
   echo $dir . " is our directory.<br><br>\n";
   echo "[...IN PROGRESS...]<br><br>";

   $file_list = '';
   $stack[] = $dir;
 
   while ($stack) {
      $current_dir = array_pop($stack);
      if ($dh = opendir($current_dir)) {
          while (($file = readdir($dh)) !== false) {
              if ($file !== '.' AND $file !== '..') {
                  $current_file = "{$current_dir}/{$file}";
               if (is_dir($current_file)) {
                      // BEG ADD PATH   
                   $mode = getmod($current_file);    //Get the mode
                      $HasPubRead = hasmod($mode,4);
                   if ($HasPubRead || $listall) {    // Can the public read this dir?
                  //======================================
                    $ch = true;
                  $take = 0;
                       // Change the mode:
                     if ($HasPubRead) {
                          $take = 4;         // Value for Public Read. 4 is the same in octal and decimal.
                          if (!$testrun) {
                              $ch = chmod($current_file, $mode-$take);
                          }
                      }

                    echo $current_file . ",current=" . decoct($mode) .
                        (($mode!==$mode-$take) ? ",new=" . decoct($mode-$take) : '') .
                        ($ch ? '' : ',FAILED') . "<br>\n";
                   } // end if hasmod
                   // END ADD PATH                          
                      $stack[] = $current_file;
                  } // if if_dir
              } //if ($file !== '.' AND $file !== '..')
          } //while (($file = readdir($dh)) !== false)
      } //if ($dh = opendir($current_dir))
} // while ($stack)

    echo "<br>COMPLETE @ " . date("F j, Y, h:i:s A") . "<br>\n";
return;
   //return $path_list;
} // end function

//-------------------------------------------------------
    //listall Show all folders, even one's we're not going to process?
    //testrun Do a test run without making any changes
    pathlock($_SERVER["DOCUMENT_ROOT"],false,true); // listall?=false, testrun?=true

?>
redeyeleader
11-Feb-2007 12:05
Here's a version that works with PHP 5.x - I use this to watermark images on a shared server.

<?php
// Connect to the FTP to chmod the file via FTP

$ftpUserName = 'username';
$ftpUserPass = 'userpass';
$ftpServer = 'ftp.example.com';

  $ftpConn = ftp_connect($ftpServer);
 
  if (!$ftpConn) {
    die("Unable to connect to $ftpServer");
  }

if (@ftp_login($conn_id, $ftpUserName, $ftpUserPass)) {
   echo "Connected as $ftpUserName @ $ftpServer";
}
else {
   echo "Couldn't connect as $ftpUserName";
   ftp_close($ftpConn);
   die("Closed connection to $ftpServer");
}

//Now change permissions to 666 or whatever you need

echo ftp_chmod($ftpConn, 0666, $ftpFilename) ? "CHMOD successful!" : 'Error';

// do what you need here

//Now change permissions back to 644 or whatever
echo ftp_chmod($ftpConn, 0644, $ftpFilename) ? "CHMOD successful!" : 'Error';

// Close the connection
ftp_close($conn_id);
?>
hodgman at ali dot com dot au
18-Jan-2007 01:06
My PHP script refused to delete read-only files (which is probably a good thing), but I couldnt find out how to fix this on windows.

The solution is simple, i just replaced
<?php @unlink( $entry ); ?>
with:
<?php
                @chmod( $entry, 0777 );
                @unlink( $entry );
?>

chmod isnt supposed to work on windows, but 0777 seems to clear the read only flag, and 0444 seems to set the read only flag.
info at web-in-time dot eu
05-Jan-2007 05:11
As you might have noticed there is a minor bug in webmaster at danopia dot 5gigs dot com's code:

You have to set $ftp_root variable outside the function chmod_open() and have to set it as global within the chmod_file() function.

With these patches the code really works fine. THX!

Ben
webmaster at danopia dot 5gigs dot com
03-Jan-2007 10:20
Thanks for your code, "imoldgreg at o2 dot co dot uk". I am using it for an instalation script that has to CHMOD a bunch of files. I have found it faster to use the same connectino for each, as shown below.

<?php

// Thanks to "imoldgreg at o2 dot co dot uk" for the base 'CHMOD via FTP' script.

function chmod_open()
{
    // Use your own FTP info
    $ftp_user_name = 'chmod@XXXXXXXXX.com';
    $ftp_user_pass = 'XXXXXXXXXX';
    $ftp_root = '/';
    $ftp_server = 'localhost';
    $conn_id = ftp_connect($ftp_server);
    $login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);
    return $conn_id;
}

function chmod_file($conn_id, $permissions, $path)
{
    if (ftp_site($conn_id, 'CHMOD ' . $permissions . ' ' . $ftp_root . $path) !== false)
    {
        return TRUE;
    }
    else
    {
        return FALSE;
    }
}

function chmod_close($conn_id)
{
    ftp_close($conn_id);
}

// CHMOD the required setup files

// Connect to the FTP
$conn_id = chmod_open();

// CHMOD each file and echo the results
echo chmod_file($conn_id, 777, 'master/cache/') ? 'CHMODed successfully!' : 'Error';
echo chmod_file($conn_id, 777, 'master/files/') ? 'CHMODed successfully!' : 'Error';
echo chmod_file($conn_id, 777, 'master/store/') ? 'CHMODed successfully!' : 'Error';
echo chmod_file($conn_id, 766, 'master/config.php') ? 'CHMODed successfully!' : 'Error';
echo chmod_file($conn_id, 777, 'master/images/avatars/upload/') ? 'CHMODed successfully!' : 'Error';

// Close the connection
chmod_close($conn_id);

?>

Here, the same FTP connection is used for each CHMOD command, making the execute time lower. This is essential for me, since my script is also copying a bunch of files.
imoldgreg at o2 dot co dot uk
01-Dec-2006 09:32
an update to 'neil at 11 out of 10's code for changing mode using FTP.

changes: proper array added within the function (better for those of us who only need to connect to one ftp server) so only the mode and directory name need to be passed.

the octal added, for completeness and predictable stability.

function changemode($xcite)
{
$ftp_details = array(
ftp_user_name => 'username',
ftp_user_pass => 'password',
ftp_user_root => '/public_html/',
ftp_server => 'ftp.something.org'
);

$path = "public";
$mod = intval($xcite, 8);

   // extract ftp details (array keys as variable names)
   extract ($ftp_details);
  
   // set up basic connection
   $conn_id = ftp_connect($ftp_server);
  
   // login with username and password
   $login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);
  
   // try to chmod $path directory
   if (ftp_site($conn_id, 'CHMOD '.$mod.' '.$ftp_root.$path) !== false) {
       $success=TRUE;
   }
   else {
       $success=FALSE;
   }

   // close the connection
   ftp_close($conn_id);
    return $success;
}

then call it where required, an example:

changemode(777, directory);
           
if (@copy("$tempname", "$fullfilename")) $done = "yes";

changemode(755, directory);

for those of you, like me, who were looking for a way to make an 'un-hackable' uploader, here's the closest i got, now for a field test, good luck!
NeoSmart Technologies
25-Jul-2006 06:08
The program mentioned below (CHMOD-Win) has been rewritten since, and CHMOD-Win version 3.0 is available for download at http://neosmart.net/dl.php?id=4

It is a conversion utility for CHMOD on Windows and ACL on Linux, comes in handy for installing commercial scripts or defining security policies.
neil at 11 out of 10
12-Apr-2006 03:20
If you get a warning like chmod(): Operation not permitted in /home/folder/public_html/admin/includefiles/fileupload.php on line 24

You can use the ftp_site() function to send a CHMOD command through.
<?php

$ftp_details['ftp_user_name'] = $row['username'];
$ftp_details['ftp_user_pass'] = $row['password'];
$ftp_details['ftp_root'] = '/public_html/';
$ftp_details['ftp_server'] = 'ftp'.$_SERVER['HTTP_HOST'];

function chmod_11oo10($path, $mod, $ftp_details)
{
    // extract ftp details (array keys as variable names)
    extract ($ftp_details);
   
    // set up basic connection
    $conn_id = ftp_connect($ftp_server);
   
    // login with username and password
    $login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass);
   
    // try to chmod $path directory
    if (ftp_site($conn_id, 'CHMOD '.$mod.' '.$ftp_root.$path) !== false) {
        $success=TRUE;
    }
    else {
        $success=FALSE;
    }

    // close the connection
    ftp_close($conn_id);
    return $success;
}
?>
The key thing to remember is that the document root and the ftp root are not the same.
e.g. document root may be "/home/folder/public_html/"
but the ftp root might be "/public_html/"

Hope this helps someone.  You might need this solution if you are on a shared server.
memp
23-Aug-2005 06:04
If you are storing your mode in a variable like

$mode = 0755;

you will run into the inevitable octal mode problem.  An easy way around that is to use the octdec() function.

chmod("some_filename.ext", octdec($mode));
masha at mail dot ru
11-Jul-2005 12:23
Usefull reference:

Value    Permission Level
400    Owner Read
200    Owner Write
100    Owner Execute
40    Group Read
20    Group Write
10    Group Execute
4    Global Read
2    Global Write
1    Global Execute

(taken from http://www.onlamp.com/pub/a/php/2003/02/06/php_foundations.html)
alex at feidesign dot com
01-Apr-2005 08:20
If you cannot chmod files/directories with PHP because of safe_mode restrictions, but you can use FTP to chmod them, simply use PHP's FTP-functions (eg. ftp_chmod or ftp_site) instead. Not as efficient, but works.
info at rvgate dot nl
03-Feb-2005 09:12
When using ftp_rawlist, in order to get the chmod number from the attributes, i use this code:

<?php
function chmodnum($mode) {
    $realmode = "";
    $legal =  array("","w","r","x","-");
    $attarray = preg_split("//",$mode);
    for($i=0;$i<count($attarray);$i++){
        if($key = array_search($attarray[$i],$legal)){
            $realmode .= $legal[$key];
        }
    }
    $mode = str_pad($realmode,9,'-');
    $trans = array('-'=>'0','r'=>'4','w'=>'2','x'=>'1');
    $mode = strtr($mode,$trans);
    $newmode = '';
    $newmode .= $mode[0]+$mode[1]+$mode[2];
    $newmode .= $mode[3]+$mode[4]+$mode[5];
    $newmode .= $mode[6]+$mode[7]+$mode[8];
    return $newmode;
}
?>
some examples:

drwxr-xr-x => 755
drwxr-xr-x => 755
dr-xr-xr-x => 555
drwxr-xr-x => 755
drwxr-xr-x => 755
drwxr-xr-x => 755
drwxr-xr-x => 755
drwxrwxrwt => 776
drwxr-xr-x => 755
drwxr-xr-x => 755
lrwxrwxrwx => 777

used some of already posted code...
haasje at welmers dot net
28-Nov-2004 04:09
For recursive chmod'ing see the function below.
Only really usefull when chmod'ing a tree containing directories only, jet, since you don't want an executable bit on a regular file. Who completes the function so it's accepting strings like "g+w", and it's as usefull as unix "chmod -R" ? ;-)

<?php

function chmod_R($path, $filemode) {
    if (!is_dir($path))
       return chmod($path, $filemode);

    $dh = opendir($path);
    while ($file = readdir($dh)) {
        if($file != '.' && $file != '..') {
            $fullpath = $path.'/'.$file;
            if(!is_dir($fullpath)) {
              if (!chmod($fullpath, $filemode))
                 return FALSE;
            } else {
              if (!chmod_R($fullpath, $filemode))
                 return FALSE;
            }
        }
    }
 
    closedir($dh);
   
    if(chmod($path, $filemode))
      return TRUE;
    else
      return FALSE;
}
?>
PerfectWeb
23-Nov-2004 11:58
As noted by others below... 1) you cannot pass a string to chmod() as the mode, and 2) decimals work as well as octals for the mode.

If you need to come up with the mode on the fly (maybe based on user input) and want to use something like:

$mode = '0'.$owner.$group.$public;

you can use your $mode (which is a string) with chmod like this:

<?php
 // octal mode in a string i.e. '0755'
 $mode = '0'.$owner.$group.$public;

 $mode_dec = octdec($mode);    // convert octal mode to decimal
 chmod($filename, $mode_dec);
?>
fernando at gym-group dot com
12-Nov-2004 11:10
about chmod,
Problably you have a local server to simulate your scripts before upload them to the server. No matter if you use Apache under windows or IIS ,  a chmod instruction like chmod($filename,O777) may not work because windows does not handle that kind of permission's format.
So being in your local server, if you have a only read file and you try to erase, it will show that you dont have permissions even when you have already executed your chmod instrucction correctly. Just up the script it must work well in your internet server if it is a linux machine

sobre chmod,
Probablemente usas un servidor local para probar tus scripts antes de subirlos al servidor en internet. No importa si usas Apache bajo windows o IIS, una instruccion como chmod(nombre_archivo,O777) podr no trabajar por que windows no maneja esa estructura para definir los permisos.
Estando en tu servidor local, si tienes un archivo de solo lectura y tratas de borrarlo,  se mostrar un error diciendo que no tienes permisos an despes de haber ejecutado chmod correctamente. Sube tu script, si tu servidor es una mquina linux, el script trabajar sin problemas en internet.

Fernando Yepes C.
Oliver Hankeln
01-Jul-2004 11:21
Well, you don't need octals.
You need a value that can easily computed and remembered if printed in octal.
511 (decimal) is the same as 777 (octal).
So it's the same wether you write
chmod("foo",511)
or
chmod("foo",0777)

The latter is just better readable.
raven_25041980 at yahoo dot com
25-May-2004 01:45
If you have a mode as a string, chmod will insanely mess up your permissions. Instead of using

<?php

@chmod($file_or_dir_name, $mode);

?>

use

<?php

@chmod(file_or_dir_name, intval($mode, 8));

?>

where 8 -> the base to convert into. You need octals, baby, for chmod...

More on intval here: http://www.php.net/manual/en/function.intval.php
agrenier at assertex dot com
02-Apr-2004 09:17
If you find that chmod does not work on your file and that a new file cannot be created, first try to chmod the directory where the file is being created to 0666/0777. Then PHP should be able to write/append files with mode 0644.
agrenier at assertex dot com
02-Apr-2004 09:11
This function will chmod a $filename before writing to it if:

1 - It exists
2 - It is not writeable
3 - PHP has permission to chmod files

If PHP can't chmod, then the script will end. Otherwise it will attempt to write to a new file.

<?php

    function file_write($filename, $flag, &$content) {
        if (file_exists($filename)) {
            if (!is_writable($filename)) {
                if (!chmod($filename, 0666)) {
                     echo "Cannot change the mode of file ($filename)";
                     exit;
                };
            }
        }
        if (!$fp = @fopen($filename, $flag)) {
            echo "Cannot open file ($filename)";
            exit;
        }
        if (fwrite($fp, $content) === FALSE) {
            echo "Cannot write to file ($filename)";
            exit;
        }
        if (!fclose($fp)) {
            echo "Cannot close file ($filename)";
            exit;
        }
    }

?>
Jazeps Basko
27-Jan-2004 11:37
To convert 'rwxr-xr--' to a number representation of chmod, i use this:
<?php
    function chmodnum($mode) {
        $mode = str_pad($mode,9,'-');
        $trans = array('-'=>'0','r'=>'4','w'=>'2','x'=>'1');
        $mode = strtr($mode,$trans);
        $newmode = '';
        $newmode .= $mode[0]+$mode[1]+$mode[2];
        $newmode .= $mode[3]+$mode[4]+$mode[5];
        $newmode .= $mode[6]+$mode[7]+$mode[8];
        return $newmode;
    }
?>
pmichaud at pobox dot com
20-Apr-2003 06:45
In the previous post, stickybit avenger writes:
    Just a little hint. I was once adwised to set the 'sticky bit', i.e. use 1777 as chmod-value...

Note that in order to set the sticky bit on a file one must use '01777' (oct) and not '1777' (dec) as the parameter to chmod:

<?php
    chmod("file",01777);   // correct
     chmod("file",1777);    // incorrect, same as chmod("file",01023), causing no owner permissions!
?>

Rule of thumb: always prefix octal mode values with a zero.
sticky bit avenger
12-Mar-2003 07:30
Just a little hint. I was once adwised to set the 'sticky bit', i.e. use 1777 as chmod-value. Do NOT do this if you don't have root privileges. When 'sticky bit' is set ONLY the fileuser can delete it afterwards, typically 'httpd' or something like that in case of an upload-script for example. I was unaware of this and actually had to make a script for deleting these files as I could not do this from ftp/ssh even though I did have read/write/execute access to both files and folders. Use simply '0777' or similiar.
Half-Dead at nospam dot com
08-Nov-2002 06:42
[Editor's note:
That is due the fact Win32 systems treat premissions. You do not really have any other levels but read-only.

Maxim]


On WinME with apache chmod also works to a certain limit.

What happens is that apparently only the first number is counted, so 0666 (read-write) is the same as 0777, 0644, 0600, etc, and 0444 (read-only) is the same as 477, 400, etc.

..didn't test 0500 series
FF7Cayn at gmx dot de
28-Oct-2001 08:09
It does work on Windows.
I use Win 98 with the Sambar Server.
The only chmods allowed are the 775 and 666 mod. 775 for non-writeable and 666 for writeable. The only thing is that the usergroups doesn't work.
Note: the 0 at the start doesn't work with windows. use only the decimal kind.
Have fun :)
jon at zend dot com
15-Oct-2001 11:37
if 'mode' is held in a variable and is and octal value you need to convert it to decimal before passing it to the function:
chmod ($filename, octdec($mode))
gnettles2 at home dot com
25-Aug-2001 02:20
Usually when you're trying to write to af file, you'll need to chmod the file to something like 666 or 755. You can use a command to chmod the file for you, which is especially useful when you're making a script where you're setting it up so that your users don't have to peform a bunch of actions to setup the script. When i wrote my news program script, I only had two files. install.php and config.php. All you had to do was chmod install.php to 666 and open it up in a web browser and answer a few questions. The script itself setup the rest of the files and chmodded them for you.
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