stat

digitalaudiorock at hotmail dot com (2008-12-12 08:23:51)

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

webmaster at askapache dot com (2008-11-26 01:20:17)

This is a souped up 'stat' function based on 
many user-submitted code snippets and 
@ http://www.askapache.com/security/chmod-stat.html 

Give it a filename, and it returns an array like stat. 

<?php

function alt_stat($file) {
 
 clearstatcache();
 $ss=@stat($file);
 if(!$ss) return false; //Couldnt stat file
 
 $ts=array(
  0140000=>'ssocket',
  0120000=>'llink',
  0100000=>'-file',
  0060000=>'bblock',
  0040000=>'ddir',
  0020000=>'cchar',
  0010000=>'pfifo'
 );
 
 $p=$ss['mode'];
 $t=decoct($ss['mode'] & 0170000); // File Encoding Bit
 
 $str =(array_key_exists(octdec($t),$ts))?$ts[octdec($t)]{0}:'u';
 $str.=(($p&0x0100)?'r':'-').(($p&0x0080)?'w':'-');
 $str.=(($p&0x0040)?(($p&0x0800)?'s':'x'):(($p&0x0800)?'S':'-'));
 $str.=(($p&0x0020)?'r':'-').(($p&0x0010)?'w':'-');
 $str.=(($p&0x0008)?(($p&0x0400)?'s':'x'):(($p&0x0400)?'S':'-'));
 $str.=(($p&0x0004)?'r':'-').(($p&0x0002)?'w':'-');
 $str.=(($p&0x0001)?(($p&0x0200)?'t':'x'):(($p&0x0200)?'T':'-'));
 
 $s=array(
 'perms'=>array(
  'umask'=>sprintf("%04o",@umask()),
  'human'=>$str,
  'octal1'=>sprintf("%o", ($ss['mode'] & 000777)),
  'octal2'=>sprintf("0%o", 0777 & $p),
  'decimal'=>sprintf("%04o", $p),
  'fileperms'=>@fileperms($file),
  'mode1'=>$p,
  'mode2'=>$ss['mode']),
 
 'owner'=>array(
  'fileowner'=>$ss['uid'],
  'filegroup'=>$ss['gid'],
  'owner'=>
  (function_exists('posix_getpwuid'))?
  @posix_getpwuid($ss['uid']):'',
  'group'=>
  (function_exists('posix_getgrgid'))?
  @posix_getgrgid($ss['gid']):''
  ),
 
 'file'=>array(
  'filename'=>$file,
  'realpath'=>(@realpath($file) != $file) ? @realpath($file) : '',
  'dirname'=>@dirname($file),
  'basename'=>@basename($file)
  ),

 'filetype'=>array(
  'type'=>substr($ts[octdec($t)],1),
  'type_octal'=>sprintf("%07o", octdec($t)),
  'is_file'=>@is_file($file),
  'is_dir'=>@is_dir($file),
  'is_link'=>@is_link($file),
  'is_readable'=> @is_readable($file),
  'is_writable'=> @is_writable($file)
  ),
  
 'device'=>array(
  'device'=>$ss['dev'], //Device
  'device_number'=>$ss['rdev'], //Device number, if device.
  'inode'=>$ss['ino'], //File serial number
  'link_count'=>$ss['nlink'], //link count
  'link_to'=>($s['type']=='link') ? @readlink($file) : ''
  ),
 
 'size'=>array(
  'size'=>$ss['size'], //Size of file, in bytes.
  'blocks'=>$ss['blocks'], //Number 512-byte blocks allocated
  'block_size'=> $ss['blksize'] //Optimal block size for I/O.
  ), 
 
 'time'=>array(
  'mtime'=>$ss['mtime'], //Time of last modification
  'atime'=>$ss['atime'], //Time of last access.
  'ctime'=>$ss['ctime'], //Time of last status change
  'accessed'=>@date('Y M D H:i:s',$ss['atime']),
  'modified'=>@date('Y M D H:i:s',$ss['mtime']),
  'created'=>@date('Y M D H:i:s',$ss['ctime'])
  ),
 );
 
 clearstatcache();
 return $s;
}

?>

|=---------[ Example Output ]

Array(
[perms] => Array
  (
  [umask] => 0022
  [human] => -rw-r--r--
  [octal1] => 644
  [octal2] => 0644
  [decimal] => 100644
  [fileperms] => 33188
  [mode1] => 33188
  [mode2] => 33188
  )
 
[filetype] => Array
  (
  [type] => file
  [type_octal] => 0100000
  [is_file] => 1
  [is_dir] =>
  [is_link] =>
  [is_readable] => 1
  [is_writable] => 1
  )
 
[owner] => Array
  (
  [fileowner] => 035483
  [filegroup] => 23472
  [owner_name] => askapache
  [group_name] => grp22558
  )
 
[file] => Array
  (
  [filename] => /home/askapache/askapache-stat/htdocs/ok/g.php
  [realpath] =>
  [dirname] => /home/askapache/askapache-stat/htdocs/ok
  [basename] => g.php
  )
 
[device] => Array
  (
  [device] => 25
  [device_number] => 0
  [inode] => 92455020
  [link_count] => 1
  [link_to] =>
  )
 
[size] => Array
  (
  [size] => 2652
  [blocks] => 8
  [block_size] => 8192
  )
 
[time] => Array
  (
  [mtime] => 1227685253
  [atime] => 1227685138
  [ctime] => 1227685253
  [accessed] => 2008 Nov Tue 23:38:58
  [modified] => 2008 Nov Tue 23:40:53
  [created] => 2008 Nov Tue 23:40:53
  )
)

antonixyz at gmx dot net (2008-07-21 02:19:08)

<?php
$stat = stat($filepath);
$mode = $stat[2];
?>
is identical to:
<?php $mode = fileperms($filepath); ?>

at least on my linux box.

mail4rico at gmail dot com (2008-04-24 11:19:14)

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.

sh at advisa dot fr (2008-04-24 05:35:12)

Another possibility to get the whole dir size, using "du" on Linux
$size = exec("du -sm /your/path | awk '{print $1}'");

Hellhound (2008-03-03 02:16:58)

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);

JulieC (2007-01-30 19:21:50)

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.

piranha-php dot net at thoughtcrime dot us (2006-07-16 17:04:28)

stat() returns a file's _status_, not its _statistics_. "Statistics" implies information interpreted from the data of several files, not concrete meaning from a single file. Both Linux and POSIX manual pages for stat() list the name as "stat - get file status," and do not mention the word "statistic" anywhere.

hugues dot larrive at gmail dot com (2006-06-08 13:49:10)

salisbm at hotmail dot com said :
(...)to see if the file is a directory, after calling fstat, I do:
if ($fstats[mode] & 040000)
  ... this must be a directory

Then I say no no no no... it can be a directory or a named pipe, or a block spécial ...

The good code for this thing is :

<?php
if(($fstat['mode'] & 0170000) == 040000) echo "Be sure it is a directory !";
?>

Sorry for very ugly english ;)
@+

(2006-05-16 10:10:43)

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.

marting.dc AT gmail.com (2006-01-28 17:08:20)

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';
?>

admin at smitelli dot com (2005-11-02 23:27:51)

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.

com dot gmail at algofoogle (2005-07-21 18:06:15)

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...

mpb dot mail at gmail dot com (2005-07-17 15:10:44)

If you are working with files larger than 2GB (and PHP's integer type is only 32 bits on your system) then you can try the following to get floating point sizes:
On FreeBSD:
$size = (float) exec ('stat -f %z '. escapeshellarg ($path));
On Linux:
$size = (float) exec ('stat -c %s '. escapeshellarg ($path));
(The other example that uses "ls" and "awk" does not properly escape the filename, but should work otherwise.)

mao at nospam dot com (2005-06-07 05:53:15)

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);
?>

guillermo martinez (2005-01-30 10:24:42)

stat() and SELinux,
You can have troubles to use the stat() function if the SELinux is enabled, so check the SELinux documentation or turn it off.

(2004-11-10 19:41:39)

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;
}

svend at svendtofte dot com (2004-10-09 16:31:38)

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.

salisbm at hotmail dot com (2003-08-11 17:21:00)

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

ian at eiloart dot com (1999-07-23 08:52:30)

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.