03-11-2002
touch a_new_empty_file.txt
will create a null file, or will change the last_access_time on that file.
> the_file_I_want_nothing_in.txt
will both empty a full file or create a null file. -mk
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TOUCH(3) 1 TOUCH(3)
touch - Sets access and modification time of file
SYNOPSIS
bool touch (string $filename, [int $time = time()], [int $atime])
DESCRIPTION
Attempts to set the access and modification times of the file named in the $filename parameter to the value given in $time. Note that the
access time is always modified, regardless of the number of parameters.
If the file does not exist, it will be created.
PARAMETERS
o $filename
- The name of the file being touched.
o $time
- The touch time. If $time is not supplied, the current system time is used.
o $atime
- If present, the access time of the given filename is set to the value of $atime. Otherwise, it is set to the value passed to the
$time parameter. If neither are present, the current system time is used.
RETURN VALUES
Returns TRUE on success or FALSE on failure.
CHANGELOG
+--------+---------------------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------------------------+
| 5.3.0 | |
| | |
| | It became possible to change the modification |
| | time of a directory under Windows. |
| | |
+--------+---------------------------------------------------+
EXAMPLES
Example #1
touch(3) example
<?php
if (touch($filename)) {
echo $filename . ' modification time has been changed to present time';
} else {
echo 'Sorry, could not change modification time of ' . $filename;
}
?>
Example #2
touch(3) using the $time parameter
<?php
// This is the touch time, we'll set it to one hour in the past.
$time = time() - 3600;
// Touch the file
if (!touch('some_file.txt', $time)) {
echo 'Whoops, something went wrong...';
} else {
echo 'Touched file with success';
}
?>
NOTES
Note
Note that time resolution may differ from one file system to another.
Warning
Prior to PHP 5.3.0 it was not possible to change the modification time of a directory with this function under Windows.
PHP Documentation Group TOUCH(3)