(PHP 5 >= 5.3.0, PHP 7, PHP 8)
header_remove — Remove previously set headers
$name = null): voidRemoves an HTTP header previously set using header().
name
       The header name to be removed. When null, all previously set headers are removed.
      
Note: This parameter is case-insensitive.
No value is returned.
| Version | Description | 
|---|---|
| 8.0.0 | nameis nullable now. | 
Example #1 Unsetting specific header.
<?php
header("X-Foo: Bar");
header("X-Bar: Baz");
header_remove("X-Foo"); 
?>
The above example will output something similar to:
X-Bar: Baz
Example #2 Unsetting all previously set headers.
<?php
header("X-Foo: Bar");
header("X-Bar: Baz");
header_remove(); 
?>
The above example will output something similar to:
    This function will remove all headers set by PHP,
    including cookies, session and the X-Powered-By headers.
   
Note:
Headers will only be accessible and output when a SAPI that supports them is in use.