The unlink() function is an inbuilt function in PHP which is used to delete files. It is similar to UNIX unlink() function. The $filename is sent as a parameter that needs to be deleted and the function returns True on success and false on failure.
Syntax:
unlink( $filename, $context )
Parameters: This function accepts two parameters as mentioned above and described below:
- $filename: It is a mandatory parameter which specifies the filename of the file which has to be deleted.
- $context: It is an optional parameter which specifies the context of the file handle which can be used to modify the nature of the stream.
Return Value: It returns True on success and False on failure.
Errors And Exception:
- The unlink() function generates an E_WARNING level error on failure.
- The web server user must have write permissions to the directory for using the unlink() function.
- The unlink() function returns Boolean False but many times it happens that it returns a non-Boolean value which evaluates to False.
Below programs illustrate the unlink() function in PHP:
Suppose there is a file named as “gfg.txt”
Program 1:
PHP
<?php// PHP program to delete a file named gfg.txt // using unlink() function$file_pointer = "gfg.txt";// Use unlink() function to delete a fileif (!unlink($file_pointer)) { echo ("$file_pointer cannot be deleted due to an error");}else { echo ("$file_pointer has been deleted");}?> |
Output:
gfg.txt has been deleted
Program 2:
PHP
<?php// PHP program to delete a file named gfg.txt // using unlink() function $file_pointer = fopen('gfg.txt', 'w+'); // writing on a file named gfg.txt fwrite($file_pointer, 'A computer science portal for neveropen!'); fclose($file_pointer); // Use unlink() function to delete a file if (!unlink($file_pointer)) { echo ("$file_pointer cannot be deleted due to an error"); } else { echo ("$file_pointer has been deleted"); } ?> |
Output:
Warning: unlink() expects parameter 1 to be a valid path, resource given in C:\xampp\htdocs\server.php on line 12 Resource id #3 cannot be deleted due to an error
Reference: http://php.net/manual/en/function.unlink.php
