stat

(PHP 4, PHP 5, PHP 7, PHP 8)

stat — Obtém informações sobre um arquivo

Descrição

stat(string $filename): array|false

Coleta estatísticas do arquivo informado em filename. Se filename for uma ligação simbólica, estatísticas serão do próprio arquivo, não da ligação. Antes do PHP 7.4.0, nas compilações NTS do Windows, as estatísticas size, atime, mtime e ctime statistics são da ligação simbólica, neste caso.

lstat() é idêntica a stat() exceto que ela foi baseada no estado de ligações simbólicas.

Parâmetros

filename: Caminho para o arquivo.

Valor Retornado

**Formato de retorno de **stat()** e fstat()**
Numérico	Associativo	Descrição
0	dev	número do dispositivo ***
1	ino	número do inode ***
2	mode	modo de proteção do inode *****
3	nlink	número de ligações
4	uid	id de usuário do proprietário *
5	gid	id de grupo do proprietário *
6	rdev	tipo de dispositivo, se for inode
7	size	tamanho em bytes
8	atime	horário do último acesso (timestamp Unix)
9	mtime	horário da última modificação (timestamp Unix)
10	ctime	hora da última modificação do inode (timestamp Unix)
11	blksize	tamanho do bloco de E/S no sistema de arquivos **
12	blocks	número de blocos de 512 bytes alocados **

* No Windows será sempre 0.

** Válido apenas em sistemas que suportam o tipo st_blksize type - outros sistemas (ex.: Windows) retornam -1.

*** No Windows, a partir do PHP 7.4.0, este é o número de série do volume que contém o arquivo, que é um inteiro de 64-bits sem sinal, ou seja, pode sobrecarregar. Anteriormente, era uma representação numérica da letra do dispositivo (ex.: 2 para C:) para stat(), e 0 para lstat().

**** No Windows, a partir do PHP 7.4.0, este é o identificador associado com o arquivo, que é um inteiro de 64-bits sem sinal, ou seja, pode sobrecarregar. Anteriormente, era sempre 0.

***** No Windows, o bit de permissão de escrita é definido de acordo com o atributo de somente-leitura do arquivo, e o mesmo valor é reportado para todos os usuários, grupos e proprietários. A ACL não é levada em consideração, contrário a is_writable().

O valor de mode contém informação lida por várias funções. Quando escrita em octal, começando da direita, os primeiros três dígitos são retornados por chmod(). O dígito seguinte é ignorado pelo PHP. Os dois dígitos seguintes indicam o tipo de arquivo:

**Tipos de arquivo para `mode`**
`mode` em octal	Significado
`0140000`	socket
`0120000`	ligação
`0100000`	arquivo normal
`0060000`	dispositivo de bloco
`0040000`	diretório
`0020000`	dispositivo de caracteres
`0010000`	fifo

Por exemplo, um arquivo normal poderia ser 0100644 e um diretório poderia ser 0040755.

Em caso de erro, stat() retorna false.

Nota: Como o tipo inteiro do PHP possui sinal e muitas plataformas usam números inteiros de 32 bits, algumas funções do sistema de arquivos podem retornar resultados inesperados para arquivos maiores que 2GB.

Erros/Exceções

Em caso de falha, um E_WARNING é emitido.

Registro de Alterações

Versão	Descrição
7.4.0	No Windows, o número do dispositivo agora é o número de série do volume que contém o arquivo, e o número do inode é o identificador associado com o arquivo.
7.4.0	As estatísticas `size`, `atime`, `mtime` e `ctime` de ligações simbólicas agora são sempre aquelas do alvo. Anteriormente não era o caso para compilações NTS do Windows.

Exemplos

Exemplo #1 stat() example

<?php
/* Obtém estatística sobre o arquivo */
$stat = stat('C:\php\php.exe');

/*
 * Mostra o horário de acesso ao arquivo, é o mesmo que
 * chamar fileatime()
 */
echo 'Horário de acesso: ' . $stat['atime'];

/*
 * Mostra o horário de modificação do arquivo, é o mesmo que
 * chamar filemtime()
 */
echo 'Horário de modificação: ' . $stat['mtime'];

/* Mostra o número de dispositivo */
echo 'Número de dispositivo: ' . $stat['dev'];
?>

Exemplo #2 Usando informação de stat() junto com a função touch()

<?php
/* Obtém estatística sobre o arquivo */
$stat = stat('C:\php\php.exe');

/* Falhou a obtenção de estatística? */
if (!$stat) {
    echo 'stat() falhou...';
} else {
    /*
     * Queremos o horário de acesso 1 semana
     * depois do atual.
     */
    $atime = $stat['atime'] + 604800;

    /* Toca o arquivo */
    if (!touch('some_file.txt', time(), $atime)) {
        echo 'Falha ao tocar o arquivo...';
    } else {
        echo 'touch() retorno com sucesso...';
    }
}
?>

Notas

Nota:
Note que a resolução de tempo pode variar de um sistema de arquivos para outro.

Nota: Os resultados desta função são armazenados em cache. Consulte a função clearstatcache() para mais detalhes.

Dica

A partir do PHP 5.0.0, esta função também pode ser usada com alguns wrappers URL. Consulte os Protocolos e Wrappers suportados para determinar quais wrappers suportam a família de funções stat().

Veja Também

lstat() - Obtém informações sobre um arquivo ou ligação simbólica
fstat() - Lê informações sobre um arquivo usando um ponteiro de arquivo aberto
filemtime() - Obtém o horário de modificação do arquivo
filegroup() - Lê o grupo do arquivo
SplFileInfo

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User Contributed Notes 18 notes

down

webmaster at askapache dot com ¶

10 years ago


On GNU/Linux you can retrieve the number of currently running processes on the machine by doing a stat for hard links on the '/proc' directory like so:

$ stat -c '%h' /proc
118

You can do the same thing in php by doing a stat on /proc and grabbing the [3] 'nlink' - number of links in the returned array.

Here is the function I'm using, it does a clearstatcache() when called more than once.

<?php

/**
 * Returns the number of running processes
 *
 * @link http://php.net/clearstatcache
 * @link http://php.net/stat  Description of stat syntax.
 * @author http://www.askapache.com/php/get-number-running-proccesses.html
 * @return int
 */
function get_process_count() {
  static $ver, $runs = 0;
  
  // check if php version supports clearstatcache params, but only check once
  if ( is_null( $ver ) )
    $ver = version_compare( PHP_VERSION, '5.3.0', '>=' );
 
  // Only call clearstatcache() if function called more than once */
  if ( $runs++ > 0 ) { // checks if $runs > 0, then increments $runs by one.
    
    // if php version is >= 5.3.0
    if ( $ver ) {
      clearstatcache( true, '/proc' );
    } else {
      // if php version is < 5.3.0
      clearstatcache();
    }
  }
  
  $stat = stat( '/proc' );
 
  // if stat succeeds and nlink value is present return it, otherwise return 0
  return ( ( false !== $stat && isset( $stat[3] ) ) ? $stat[3] : 0 );
}

?>

Example #1 get_process_count() example

<?php
$num_procs = get_process_count();
var_dump( $num_procs );
?>

The above example will output:

int(118)

Which is the number of processes that were running.

down

webmaster at askapache dot com ¶

15 years ago

down

admin at smitelli dot com ¶

19 years ago


There's an important (yet little-known) problem with file dates on Windows and Daylight Savings. This affects the 'atime' and 'mtime' elements returned by stat(), and it also affects other filesystem-related functions such as fileatime() and filemtime().

During the winter months (when Daylight Savings isn't in effect), Windows will report a certain timestamp for a given file. However, when summer comes and Daylight Savings starts, Windows will report a DIFFERENT timestamp! Even if the file hasn't been altered at all, Windows will shift every timestamp it reads forward one full hour during Daylight Savings.

This all stems from the fact that M$ decided to use a hackneyed method of tracking file dates to make sure there are no ambiguous times during the "repeated hour" when DST ends in October, maintain compatibility with older FAT partitions, etc. An excellent description of what/why this is can be found at http://www.codeproject.com/datetime/dstbugs.asp

This is noteworthy because *nix platforms don't have this problem. This could introduce some hard-to-track bugs if you're trying to move scripts that track file timestamps between platforms.

I spent a fair amount of time trying to debug one of my own scripts that was suffering from this problem. I was storing file modification times in a MySQL table, then using that information to see which files had been altered since the last run of the script. After each Daylight Savings change, every single file the script saw was considered "changed" since the last run, since all the timestamps were off by +/- 3600 seconds.

This one-liner is probably one of the most incorrect fixes that could ever be devised, but it's worked flawlessly in production-grade environments... Assuming $file_date is a Unix timestamp you've just read from a file:

<?php
    if (date('I') == 1) $file_date -= 3600;
?>

That will ensure that the timestamp you're working with is always consistently reported, regardless of whether the machine is in Daylight Savings or not.

down

mao at nospam dot com ¶

19 years ago


If you have ftp (and the related sftp) protocols disabled on your remote server, it can be hard figuring out how to 'stat' a remote file. The following works for me:

<?php  

$conn = ssh2_connect($host, 22);
ssh2_auth_password($conn, $user, $password);
$stream = ssh2_exec($conn, "stat $fileName > $remotedest");
ssh2_scp_recv($conn, $remotedest, $localdest);
$farray = file($localdest);
print_r($farray);
?>

down

salisbm at hotmail dot com ¶

21 years ago


I was curious how I could tell if a file was a directory... so I found on http://www.hmug.org/man/2/stat.html the following information about the mode bits:
#define S_IFMT 0170000           /* type of file */
#define        S_IFIFO  0010000  /* named pipe (fifo) */
#define        S_IFCHR  0020000  /* character special */
#define        S_IFDIR  0040000  /* directory */
#define        S_IFBLK  0060000  /* block special */
#define        S_IFREG  0100000  /* regular */
#define        S_IFLNK  0120000  /* symbolic link */
#define        S_IFSOCK 0140000  /* socket */
#define        S_IFWHT  0160000  /* whiteout */
#define S_ISUID 0004000  /* set user id on execution */
#define S_ISGID 0002000  /* set group id on execution */
#define S_ISVTX 0001000  /* save swapped text even after use */
#define S_IRUSR 0000400  /* read permission, owner */
#define S_IWUSR 0000200  /* write permission, owner */
#define S_IXUSR 0000100  /* execute/search permission, owner */

Note that these numbers are in octal format.  Then, to check to see if the file is a directory, after calling fstat, I do:

if ($fstats[mode] & 040000)
  ... this must be a directory

down

ian at eiloart dot com ¶

25 years ago


Here's what the UNIX man page on stat has to say about the difference between a file change and  a file modification:



st_mtime  Time when data was last modified.  Changed by  the following  functions:   creat(),  mknod(), pipe(), utime(), and write(2).



st_ctime  Time when file status was last  changed.   Changed by  the  following  functions: chmod(), chown(), creat(), link(2), mknod(), pipe(), unlink(2), utime(), and write().



So a modification is a change in the data, whereas a change also happens if you modify file permissions and so on.

down

digitalaudiorock at hotmail dot com ¶

15 years ago


Regarding the stat() on files larger than 2GB on 32 bit systems not working, note that the behavior appears to differ between Linux and Windows.  Under Windows there's so way to know whether or not this failed.

It's been my experience that under Linux, performing a stat() on files that are too large for the integer size generates a warning and returns false.  However under Windows it silently truncates the high order bits of the size resulting in an incorrect number.  The only way you'd ever know it failed is in the event that the truncation happened to leave the sign bit on resulting in a negative size.  That is, there is _no_ reliable way to know it failed.

This is true of filesize() as well.

Tom

down

mail4rico at gmail dot com ¶

16 years ago


In response to the note whose first line is:
Re note posted by "admin at smitelli dot com"

I believe you have the conversion backwards. You should add an hour to filemtime if the system is in DST and the file is not. Conversely, you should subtract an hour if the file time is DST and the current OS time is not.

Here's a simplified, corrected version:
<?php
    function getmodtime($file) { //returns the time a file was modified.
        $mtime = filemtime($file);
        //date('I') returns 1 if DST is on and 0 if off.
        $diff = date('I')-date('I', $mtime);
        //diff =  0 if file-time and os-time are both in the same DST setting
        //diff =  1 if os is DST and file is not
        //diff = -1 if file is DST and os is not
        return $mtime + $diff*3600;
    }
?>
Here's a test:
<?php
    //create two dummy files:
    $file0 = 'file1.txt';
    $file1 = 'file2.txt';
    file_put_contents($file0, '');
    file_put_contents($file1, '');
    
    $time0=strtotime('Jan 1 2008 10:00'); echo 'Date0 (ST): ' . date(DATE_COOKIE, $time0)."\n";
    $time1=strtotime('Aug 1 2008 10:00'); echo 'Date1 (DT): ' . date(DATE_COOKIE, $time1)."\n";
    touch($file0, $time0); //set file0 to Winter (Non-DST)
    touch($file1, $time1); //set file1 to Summer (DST)
    
    $ftime0 = filemtime($file0);
    $ftime1 = filemtime($file1);
    echo "\nUncorrected: \n";
    echo 'File 0: ' . ($ftime0-$time0) ."\n";
    echo 'File 1: ' . ($ftime1-$time1) ."\n";
    //if your system adjusts for DST, then _one_ of the above should be 3600 or -3600, depending on the time of year
    
    $ftime0 = getmodtime($file0); //use filemtime correction
    $ftime1 = getmodtime($file1); //use filemtime correction
    echo "\nCorrected: \n";
    echo 'File 0: ' . ($ftime0-$time0) ."\n";
    echo 'File 1: ' . ($ftime1-$time1) ."\n";
    //both of the corrected values output should be 0.
?>

Output:
------------------------------
(when run in summer)
------------------------------
Date0 (ST): Tuesday, 01-Jan-08 10:00:00 EST
Date1 (DT): Friday, 01-Aug-08 10:00:00 EDT

Uncorrected: 
File 0: -3600
File 1: 0

Corrected: 
File 0: 0
File 1: 0
------------------------------
(when run in winter--dates omitted)
------------------------------
Uncorrected: 
File 0: 0
File 1: 3600

Corrected: 
File 0: 0
File 1: 0

In response to Re note posted by "admin at smitelli dot com",  your version below gives the following output when substituted into my test:
------------------------------
(when run in summer--dates omitted)
------------------------------
Uncorrected: 
File 0: -3600
File 1: 0

Corrected: 
File 0: -7200
File 1: 0
------------------------------
You can see that the operation is the opposite of what it should be.

down

com dot gmail at algofoogle ¶

19 years ago


Re note posted by "salisbm at hotmail dot com":

S_IFDIR is not a single-bit flag. It is a constant that relies on the "S_IFMT" bitmask. This bitmask should be applied to the "mode" parameter before comparing with any of the other "S_IF..." constants, as indicated by stat.h:

#define S_ISDIR(m)  (((m) & S_IFMT) == S_IFDIR)

That is, this approach is incorrect:

<?php
define('S_IFDIR',040000);
if ($mode & S_IFDIR)
{
  /*
    incorrect!
    format could be S_IFDIR, but also
    S_IFBLK, S_IFSOCK, or S_IFWHT.
  */
}
?>

...and should instead be:

<?php
define('S_IFMT',0170000);
define('S_IFDIR',040000);
if (S_IFDIR == ($mode & S_IFMT)) {  /* ... */  }
?>

As pointed out by "svend at svendtofte dot com", however, there is also the "is_dir" function for this purpose, along with "is_file" and "is_link" to cover the most common format types...

down

marting.dc AT gmail.com ¶

18 years ago


If you want to know a directory size, this function will help you:



<?php

function dir_size($dir)

{

    $handle = opendir($dir);

    

    while ($file = readdir($handle)) {

        if ($file != '..' && $file != '.' && !is_dir($dir.'/'.$file)) {

            $mas += filesize($dir.'/'.$file);

            } else if (is_dir($dir.'/'.$file) && $file != '..' && $file != '.') {

            $mas += dir_size($dir.'/'.$file);

        }

    }

    return $mas;

}

echo dir_size('DIRECTORIO').' Bytes';

?>

down

JulieC ¶

17 years ago


The dir_size function provided by "marting.dc AT gmail.com" works great, except the $mas variable is not initialized.  Add:

   $mas = 0;

before the while() loop.

down

svend at svendtofte dot com ¶

20 years ago


To the note of how you can figure out if a file is a folder or not, there is also the handy "is_dir" function.

down

Hellhound ¶

16 years ago


To ignore index number or name specifics.. use:

list($dev, $ino, $mode, $nlink, $uid, $gid, $rdev, $size, $atime, $mtime, $ctime, $blksize, $blocks)
         = lstat($directory_element);

down

carlos [at] encore-lab [dot] com ¶

10 years ago


stat() may not work on mounted CIFS' in 32 bit systems if you do not specify the option noserverino when mounting. E.g:

mount -t cifs -o user="user",password="password",noserverino //example.local/share /mnt/mount-point

Other functions based on stat() data such as file time functions and is_dir() are affected the same way.

This happens because if you do not specify the option noserverino the remote inode may be 64 bit-based and thus the local system cannot handle it.

down

Ray.Paseur sometimes uses Gmail ¶

3 years ago


A good explanation of the "mode" bits is given here:
https://www.php.net/manual/en/function.fileperms.php

down

Anonymous ¶

18 years ago


Re note posted by "admin at smitelli dot com"

I'm not sure how that can work all year round since you have to modify both opposing inside and outside DST based on the actual files themselves, as well as the current DST setting for the system.

e.g. using filemtime, same thing for stat.

<?php

$mtime = filemtime($file);

if (date('I') == 1) {
    // Win DST is enabled, adjust standard time 
    // files back to 'real' file UTC.
    if (date('I', $mtime) == 0) {
        $mtime -= 3600;
    }
} else {
    // Win DST is disabled, adjust daylight time 
    // files forward to 'real' file UTC.
    if (date('I', $mtime) == 1) {
        $mtime += 3600;
    }
}

echo gmdate('Y-m-d H:i:s', $mtime);

?>

Just another example of why 'not' to use windows in a server room.

down

-2

antonixyz at gmx dot net ¶

16 years ago


<?php

$stat = stat($filepath);

$mode = $stat[2];

?>

is identical to:

<?php $mode = fileperms($filepath); ?>



at least on my linux box.

down

-3

Anonymous ¶

20 years ago


If the 2GB limit is driving you crazy, you can use this complete hack.  use in place of filesize()

function file_size($file) {
  $size = filesize($file);
  if ( $size == 0)
    $size = exec("ls -l $file | awk '{print $5}'");
  return $size;
}

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