unlink
(PHP 4, PHP 5)
unlink — Удаляет файл
Описание
bool unlink
( string
$filename
[, resource $context
] )
Удаляет файл filename
. Функция похожа на функцию
unlink() Unix C. В случае ошибки будет сгенерирована ошибка уровня
E_WARNING
.
Список параметров
-
filename
-
Путь к файлу.
-
context
-
Замечание: Поддержка контекста была добавлена в PHP 5.0.0. Для описания контекстов смотрите раздел Потоки.
Возвращаемые значения
Возвращает TRUE
в случае успешного завершения или FALSE
в случае возникновения ошибки.
Список изменений
Версия | Описание |
---|---|
5.0.0 | Начиная с версии PHP 5.0.0, функция unlink() также может быть использована с некоторыми обёртками URL. Обратитесь к Поддерживаемые протоколы и обработчики (wrappers) для получения списка обёрток, которые поддерживают unlink(). |
Примеры
Пример #1 Пример простого использования unlink()
<?php
$fh = fopen('test.html', 'a');
fwrite($fh, '<h1>Hello world!</h1>');
fclose($fh);
unlink('test.html');
?>
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- Функции для работы с файловой системой
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Коментарии
To delete all files of a particular extension, or infact, delete all with wildcard, a much simplar way is to use the glob function. Say I wanted to delete all jpgs .........
<?php
foreach (glob("*.jpg") as $filename) {
echo "$filename size " . filesize($filename) . "\n";
unlink($filename);
}
?>
I have been working on some little tryout where a backup file was created before modifying the main textfile. Then when an error is thrown, the main file will be deleted (unlinked) and the backup file is returned instead.
Though, I have been breaking my head for about an hour on why I couldn't get my persmissions right to unlink the main file.
Finally I knew what was wrong: because I was working on the file and hadn't yet closed the file, it was still in use and ofcourse couldn't be deleted :)
So I thought of mentoining this here, to avoid others of making the same mistake:
<?php
// First close the file
fclose($fp);
// Then unlink :)
unlink($somefile);
?>
To anyone who's had a problem with the permissions denied error, it's sometimes caused when you try to delete a file that's in a folder higher in the hierarchy to your working directory (i.e. when trying to delete a path that starts with "../").
So to work around this problem, you can use chdir() to change the working directory to the folder where the file you want to unlink is located.
<?php
$old = getcwd(); // Save the current directory
chdir($path_to_file);
unlink($filename);
chdir($old); // Restore the old working directory
?>
Here the simplest way to delete files with mask
<?php
$mask = "*.jpg"
array_map( "unlink", glob( $mask ) );
?>
Deleted a large file but seeing no increase in free space or decrease of disk usage? Using UNIX or other POSIX OS?
The unlink() is not about removing file, it's about removing a file name. The manpage says: ``unlink - delete a name and possibly the file it refers to''.
Most of the time a file has just one name -- removing it will also remove (free, deallocate) the `body' of file (with one caveat, see below). That's the simple, usual case.
However, it's perfectly fine for a file to have several names (see the link() function), in the same or different directories. All the names will refer to the file body and `keep it alive', so to say. Only when all the names are removed, the body of file actually is freed.
The caveat:
A file's body may *also* be `kept alive' (still using diskspace) by a process holding the file open. The body will not be deallocated (will not free disk space) as long as the process holds it open. In fact, there's a fancy way of resurrecting a file removed by a mistake but still held open by a process...
This will delete all files in a directory matching a pattern in one line of code.
<?php array_map('unlink', glob("some/dir/*.txt")); ?>
unlink($fileName); failed for me .
Then i tried using the realpath($fileName) function as
unlink(realpath($fileName)); it worked
just posting it , in case if any one finds it useful .
This might seem obvious, but I was tearing my hair out with this problem - make sure the file you're trying to delete isn't currently being used. I had a script that was parsing a text file and was supposed to delete it after completing, but kept getting a permission denied error because I hadn't explicitly closed the file, hence it was technically still being "used" even though the parsing was complete.