The filemtime() function in PHP is an inbuilt function which is used to return the last time of a specified file when its content was modified. The filemtime() function returns the last time the file was changed as a Unix Timestamp on success and False on failure.
The filename is passed as a parameter to the filemtime() function. The result of the filemtime() function is cached and a function called clearstatcache() is used to clear the cache.
Syntax:
filemtime($filename)
Parameters: The filemtime() function in PHP accepts only one parameter $filename. It specifies the file which you want to check.
Return Value: It returns the last time of a file when its content was modified as a Unix Timestamp on success and False on failure.
Errors And Exception:
- The time resolution may differ from one file system to another.
- This function doesn’t works on some unix systems which have access time updates are disabled to increase performance.
Examples:
Input : echo filemtime("gfg.txt");
Output : 1525159574
Input : echo "Last modified: ".date("F d Y H:i:s.",
filemtime("gfg.txt"));
Output : Last modified: May 1 2018 07:26:14.
Below programs illustrate the filemtime() function.
Program 1:
<?php   // checking last time the contents // of a file were changed echo filemtime("gfg.txt");   ?> |
Output:
1525159574
Program 2:
<?php   // checking last time the contents // of a file were changed echo filemtime("gfg.txt");   // checking last time the contents of // a file were changed and formatting // the output of the date echo "Last modified: ".date("F d Y H:i:s.",                       filemtime("gfg.txt")); ?> |
Output:
1525159574 Last modified: May 1 2018 07:26:14.
