if you want to remove header information about php version (x-powered-by), you can use:

header_remove('x-powered-by');

alternatively, if you don't have php 5.3 installed, you can do the same thing using "header" command:

header('x-powered-by:');

don't forget the ':' character at the end of the string!

expose_php is php.ini only!

this won't work:
ini_set('expose_php',0);

works:
header_remove('x-powered-by');

If you are using this:

#!/usr/local/bin/php

You can add "-q" at the end of it and the headers will be removed, beacuse header_remove will not remove "Content-type"

#!/usr/local/bin/php -q

<?php
header_remove('Server');
phpinfo();
?>
In Apache php 8.5.6 it will only delete in the HTTP Headers Information section but the header is sent by Apache and cannot be override by php.
You can find it in the browser console, in the network section.
So you will need other various methods..
https://stackoverflow.com/questions/9000853/apache-how-to-hide-server-version-and-operation-system-from-users

When called from a command-line process, this function does nothing when passed a specific header to remove, but it does nonetheless work properly when called with no arguments to remove all headers.

Thus, when unit-testing or executing in some other test harness, if the code you are testing may call `header_remove()`, with the UOPZ and XDebug extensions loaded, you could use the following in order to more effectively test that the expected headers are set [which you would do by inspecting the array returned by `xdebug_get_headers()` after running the code under test, as `headers_list()` does not work despite the headers actually being stored internally as normal]:

<?php
uopz_set_return(
  'header_remove',
  function($name = null) {
    if ($name !== null) {
      $pattern = '/^' . preg_quote($name, '/') . ':/i';
      $headers = array_filter(
        xdebug_get_headers(),
        function($header) use($pattern) {
          return !preg_match($pattern, $header);
        }
      );
    }
    // This works to remove all headers, just not individual headers.
    header_remove();
    if ($name !== null) {
      foreach ($headers as $header) {
        header($header);
      }
    }
  },
  true
);
?>