sys_get_temp_dir

(PHP 5 >= 5.2.1, PHP 7, PHP 8)

sys_get_temp_dir返回用于临时文件的目录

说明

sys_get_temp_dir ( ) : string

返回 PHP 储存临时文件的默认目录的路径。

返回值

返回临时目录的路径。

范例

Example #1 sys_get_temp_dir() 例子

<?php
// 使用 sys_get_temp_dir() 在目录里创建临时文件
$temp_file tempnam(sys_get_temp_dir(), 'Tux');

echo 
$temp_file;
?>

以上例程的输出类似于:

C:\Windows\Temp\TuxA318.tmp

参见

  • tmpfile() - 建立一个临时文件
  • tempnam() - 建立一个具有唯一文件名的文件

User Contributed Notes

Anonymous 11-Mar-2021 01:28
On windows, when PHP is used as CLI, this function will return the temp directory for the current user e.g. C:\Users\JohnSmith\AppData\Local\Temp\9 instead of C:\Windows\Temp.
Arthur Clifford 02-Mar-2020 01:28
That is important for the purposes of building paths through concatenation to know that sys_get_temp_dir does not include a path separator at the end.

So, sys_get_temp_dir() will return whatever your temp dir is set to, by default:

/tmp

If you attempted to concatenate another dir name  temp and use the following:

mkdir(sys_get_temp_dir() . 'some_dir');

That would actually attempt to generate:
/tmpsome_dir

It would likely result in a permission error unless you are running a php script as a super user.

Instead you would want to do:
mkdir( sys_get_temp_dir() . DIRECTORY_SEPARATOR. 'some_dir' );

which would create:
/tmp/some_dir

I don't know if Windows or other platforms include a directory separator at the end. So if you are writing something a bit more general you may want to check for the path separator at the end and if it is not there append it.
besabellacyrus at gmail dot com 26-Aug-2019 01:36
using in windows this trim spaces and add ~1
OsakaWebbie 11-May-2017 03:40
If running on a Linux system where systemd has PrivateTmp=true (which is the default on CentOS 7 and perhaps other newer distros), this function will simply return "/tmp", not the true, much longer, somewhat dynamic path.
ohcc at 163 dot com 18-Jul-2016 05:17
when the sys_temp_dir directive is left unset, sys_get_temp_dir() returns C:\Windows on my Windows.
Nimja 17-Sep-2015 11:07
A very helpful thing to note when on Linux:

If you are running PHP from the commandline you can use the environment variable: TMPDIR - to change the location without touching php.ini. - This should work on most versions of PHP.

Example file: test.php
<?php
   
echo sys_get_temp_dir() . PHP_EOL;
?>

And then running:

php test.php
     /tmp
   
TMPDIR=/custom/location php test.php
    /custom/location
Anonymous 24-Apr-2015 10:44
it should be mentioned that the return value of sys_get_temp_dir() can be set using the ini-directive 'sys_temp_dir' globally as well as per directory by using
php_admin_value sys_temp_dir /path/to/tmp
royanee at yahoo dot com 11-Jun-2014 08:27
As of PHP 5.5.0, you can set the sys_temp_dir INI setting so that this function will return a useful value when the default temporary directory is not an option.
Ismail Asci 31-Jan-2014 11:56
It's not documented but this function does not  send the path with trailing spaces, actually it drops the slash if it exists.

https://github.com/php/php-src/blob/af6c11c5f060870d052a2b765dc634d9e47d0f18/main/php_open_temporary_file.c#L238
bert-jan at bugbyte dot nl 29-Mar-2010 01:06
This function does not account for virtualhost-specific modifications to the temp path and/or open_basedir:

<Virtualhost>
php_admin_value open_basedir /home/user
php_admin_value upload_tmp_dir /home/user/tmp
php_admin_value session.save_path /home/user/tmp
</Virtualhost>

Within this config it still returns /tmp
dannel at aaronexodus dot com 07-Sep-2009 01:11
There's no need to use a random name for the directory for tempnam.

Since a file and a directory can't share the same name on the filesystem, we can exploit this and simply use the name of the current file. It is guaranteed that the directory won't exist (because it's a file, of course).

<?php
if ( !function_exists('sys_get_temp_dir')) {
  function
sys_get_temp_dir() {
    if (!empty(
$_ENV['TMP'])) { return realpath($_ENV['TMP']); }
    if (!empty(
$_ENV['TMPDIR'])) { return realpath( $_ENV['TMPDIR']); }
    if (!empty(
$_ENV['TEMP'])) { return realpath( $_ENV['TEMP']); }
   
$tempfile=tempnam(__FILE__,'');
    if (
file_exists($tempfile)) {
     
unlink($tempfile);
      return
realpath(dirname($tempfile));
    }
    return
null;
  }
}
?>
Anonymous 29-Jan-2008 04:08
This function does not always add trailing slash. This behaviour is inconsistent across systems, so you have keep an eye on it.