PHP: stat - Manual

Описание

array stat ( string filename )

Собирает статистическую информацию о файле filename. Если filename является символической ссылкой, информация собирается о самом файле, а не ссылке. Функция lstat() индентична функции stat() за исключением того, что в данном случае она вернёт информацию о самой символической ссылке.

В случае ошибки, stat() вернёт FALSE. Также она выдаст предупреждение.

Возвращает массив статистической информации о файле. Массив включает следующие элементы. Индексация начинается с нуля. Также доступ к любому аттрибуту можно получить по ассоциативному ключу, который указан напротив каждого параметра; эта возможность появилась начиная с версии PHP 4.0.6:

Таблица 1. Формат результата работы функций stat() и fstat()

Числовой	Ассоциативный (начиная с PHP 4.0.6)	Описание
0	dev	номер устройства
1	ino	номер inode
2	mode	режим защиты inode
3	nlink	количество ссылок
4	uid	userid владельца
5	gid	groupid владельца
6	rdev	тип устройства, если устройство inode *
7	size	размер в байтах
8	atime	время последнего доступа (Unix timestamp)
9	mtime	время последней модификации (Unix timestamp)
10	ctime	время последнего изменения inode (Unix timestamp)
11	blksize	размер блока ввода-вывода файловой системы *
12	blocks	количество используемых блоков

* - доступен только на системах, поддерживающих тип st_blksize -- другие системы (например Windows) вернут -1.

Замечание: Результаты этой функции кэшируются. Более подробную информацию смотрите в разделе clearstatcache().

Подсказка: Начиная с PHP 5.0.0, эта функция также может быть использована с некоторыми упаковщиками url. Список упаковщиков, поддерживаемых семейством функций stat(), смотрите в Прил. M.

См. также описание функций lstat(), fstat(), filemtime() и filegroup().

stat

piranha-php dot net at thoughtcrime dot us
16-Jul-2006 05:04


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
08-Jun-2006 01:49


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 :

<?

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

?>



Sorry for very ugly english ;)

@+

16-May-2006 10:10


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
28-Jan-2006 05:08


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



<?

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
02-Nov-2005 11:27


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
21-Jul-2005 06:06


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
17-Jul-2005 03:10


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
07-Jun-2005 05:53


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
30-Jan-2005 10:24


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.

10-Nov-2004 07:41


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
09-Oct-2004 04:31


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
11-Aug-2003 05:21


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
23-Jul-1999 08:52


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.