file_get_contents
(someone delete my previous post, please - it had two bugs!)
file_put_contents() will cause concurrency problems - that is, it doesn't write files atomically (in a single operation), which sometimes means that one php script will be able to, for example, read a file before another script is done writing that file completely.
The following function was derived from a function in Smarty (http://smarty.php.net) which uses rename() to replace the file - rename() is atomic on Linux.
On Windows, rename() is not currently atomic, but should be in the next release. Until then, this function, if used on Windows, will fall back on unlink() and rename(), which is still not atomic...
<?php
define("FILE_PUT_CONTENTS_ATOMIC_TEMP", dirname(__FILE__)."/cache");
define("FILE_PUT_CONTENTS_ATOMIC_MODE", 0777);
function file_put_contents_atomic($filename, $content) {
$temp = tempnam(FILE_PUT_CONTENTS_ATOMIC_TEMP, 'temp');
if (!($f = @fopen($temp, 'wb'))) {
$temp = FILE_PUT_CONTENTS_ATOMIC_TEMP . DIRECTORY_SEPARATOR . uniqid('temp');
if (!($f = @fopen($temp, 'wb'))) {
trigger_error("file_put_contents_atomic() : error writing temporary file '$temp'", E_USER_WARNING);
return false;
}
}
fwrite($f, $content);
fclose($f);
if (!@rename($temp, $filename)) {
@unlink($filename);
@rename($temp, $filename);
}
@chmod($filename, FILE_PUT_CONTENTS_ATOMIC_MODE);
return true;
}
?>
file_put_contents
(PHP 5)
file_put_contents — Записать строку в файл
Описание
Функция идентична последовательному вызову функций fopen(), fwrite() и fclose(). Возвращаемым функцией значением является количество записанных в файл байтов.
Параметр flags может принимать значение FILE_USE_INCLUDE_PATH и/или FILE_APPEND. Используйте FILE_USE_INCLUDE_PATH с осторожностью.
Также вы можете передать (одномерный) массив в качестве параметра data . Это будет эквивалентно вызову file_put_contents($filename, join('', $array)).
Начиная с версии PHP 5.1.0, вы также можете передавать ресурс потока в качестве аргумента data . В результате оставшийся буфер этого потока будет скопирован в указанный файл. Это похоже на использование stream_copy_to_stream().
Замечание: Эта функция безопасна для обработки данных в двоичной форме.
Подсказка
Для этой функции вы можете использовать URL в качестве имени файла, если была включена опция "fopen wrappers". Смотрите более подробную информацию об определении имени файла в описании функции fopen(), а также список поддерживаемых протоколов URL в List of Supported Protocols/Wrappers.
См.также описания функций fopen(), fwrite(), fclose() и file_get_contents().
add a note
User Contributed Notesfile_put_contents
Anonymous
02-May-2008 11:06
02-May-2008 11:06
rasmus at mindplay dot dk
25-Apr-2008 02:35
25-Apr-2008 02:35
file_put_contents() will cause concurrency problems - that is, it doesn't write files atomically (in a single operation), which sometimes means that one php script will be able to, for example, read a file before another script is done writing that file completely.
The following function was derived from a function in Smarty (http://smarty.php.net) which uses rename() to replace the file - rename() is atomic on Linux.
On Windows, rename() is not currently atomic, but should be in the next release. Until then, this function, if used on Windows, will fall back on unlink() and rename(), which is still not atomic...
<?php
define("FILE_PUT_CONTENTS_ATOMIC_TEMP", dirname(__FILE__)."/cache");
define("FILE_PUT_CONTENTS_ATOMIC_MODE", 0777);
function file_put_contents_atomic($filename, $content) {
$temp = tempnam(FILE_PUT_CONTENTS_ATOMIC_TEMP, 'temp');
if (!($f = @fopen($temp, 'wb'))) {
$temp = FILE_PUT_CONTENTS_ATOMIC_TEMP . DIRECTORY_SEPARATOR . uniqid('temp');
if (!($f = @fopen($_tmp_file, 'wb'))) {
trigger_error("file_put_contents_atomic() : error writing temporary file '$temp'", E_USER_WARNING);
return false;
}
}
fwrite($f, $content);
fclose($f);
if (!@rename($temp, $filename)) {
@unlink($filename);
@rename($temp, $filename);
}
@chmod($params['filename'], FILE_PUT_CONTENTS_ATOMIC_MODE);
return true;
}
?>
the geek man at hot mail point com
03-Jan-2008 03:23
03-Jan-2008 03:23
I use the following code to create a rudimentary text editor. It's not fancy, but then it doesn't have to be. You could easily add a parameter to specify a file to edit; I have not done so to avoid the potential security headaches.
There are still obvious security holes here, but for most applications it should be reasonably safe if implemented for brief periods in a counterintuitive spot. (Nobody says you have to make a PHP file for that purpose; you can tack it on anywhere, so long as it is at the beginning of a file.)
<?php
$random1 = 'randomly_generated_string';
$random2 = 'another_randomly_generated_string';
$target_file = 'file_to_edit.php';
$this_file = 'the_current_file.php';
if ($_REQUEST[$random1] === $random2) {
if (isset($_POST['content']))
file_put_contents($target_file, get_magic_quotes_qpc() ? stripslashes($_POST['content']) : $_POST['content']);
die('<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>Editing...</title>
</head>
<body>
<form method="post" action="' . $this_file . '" />
<input type="hidden" name="' . $random1 . '" value="' . $random2 . '" />
<textarea name="content" rows="50" cols="100">' . file_get_contents($target_file) . '</textarea><br />
<input type="submit" value="Save Changes" />
</form>
</body>
</html>');
}
?>
Then simply browse to hxxp://www.example.com/{$this_file}?{$random1}={$random2}, with the appropriate values substituted for each bracketed variable. Please note that this code assumes the target file to be world writable (-rw-rw-rw- or 666) and will fail to save properly without error if it is not.
Once again, this is by no means secure or permanent, but as a quick fix for brief edits to noncritical files it should be sufficient, and its small size is a definite bonus.
egingell at sisna dot com
20-Dec-2007 07:15
20-Dec-2007 07:15
There is a better way. www.php.net/touch
Since you're not adding anything to the file,
<?php
function updateFile($filename) {
if (!file_exists($filename)) return;
touch($filename);
}
?>
me at briandichiara dot com
04-Oct-2007 12:20
04-Oct-2007 12:20
I was in need of a function that updated the last modified date in a php file. There may be a better way, but this is how I did it:
<?php
function updateFile($modFile){
if(!empty($modFile)){
if($fo = fopen($modFile, 'r')){
$source = '';
while (!feof($fo)) {
$source .= fgets($fo);
}
file_put_contents($modFile,$source);
fclose($fo);
}
}
}
?>
Curtis
21-Dec-2006 03:20
21-Dec-2006 03:20
As to the previous user note, it would be wise to include that code within a conditional statement, as to prevent re-defining file_put_contents and the FILE_APPEND constant in PHP 5:
<?php
if ( !function_exists('file_put_contents') && !defined('FILE_APPEND') ) {
...
}
?>
Also, if the file could not be accessed for writing, the function should return boolean false, not 0. An error is different from 0 bytes written, in this case.
egingell at sisna dot com
23-Jul-2006 04:11
23-Jul-2006 04:11
In reply to the previous note:
If you want to emulate this function in PHP4, you need to return the bytes written as well as support for arrays, flags.
I can only figure out the FILE_APPEND flag and array support. If I could figure out "resource context" and the other flags, I would include those too.
<?
define('FILE_APPEND', 1);
function file_put_contents($n, $d, $flag = false) {
$mode = ($flag == FILE_APPEND || strtoupper($flag) == 'FILE_APPEND') ? 'a' : 'w';
$f = @fopen($n, $mode);
if ($f === false) {
return 0;
} else {
if (is_array($d)) $d = implode($d);
$bytes_written = fwrite($f, $d);
fclose($f);
return $bytes_written;
}
}
?>
sendoshin at awswan dot com
05-Mar-2006 11:01
05-Mar-2006 11:01
To clear up what was said by pvenegas+php at gmail dot com on 11-Oct-2005 08:13, file_put_contents() will replace the file by default. Here's the complete set of rules this function follows when accessing a file:
1. Was FILE_USE_INCUDE_PATH passed in the call? If so, check the include path for an existing copy of *filename*.
2. Does the file already exist? If not, first create it in the current working directory. Either way, open the file.
3. Was LOCK_EX passed in the call? If so, lock the file.
4. Was the function called with FILE_APPEND? If not, clear the file's contents. Otherwise, move to the end of the file.
5. Write *data* into the file.
6. Close the file and release any locks.
If you don't want to completely replace the contents of the file you're writing to, be sure to use FILE_APPEND (same as fopen() with 'a') in the *flags*. If you don't, whatever used to be there will be gone (fopen() with 'w').
Hope that helps someone (and that it makes sense ^^)!
- Sendoshin
aidan at php dot net
20-May-2004 07:11
20-May-2004 07:11
This functionality is now implemented in the PEAR package PHP_Compat.
More information about using this function without upgrading your version of PHP can be found on the below link:
http://pear.php.net/package/PHP_Compat