apache_response_headers
PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8
apache_response_headers - Fetch all HTTP response headers
Manual
apache_response_headers(
Fetch all HTTP response headers. Works in the Apache, FastCGI, CLI, and FPM webservers.
Parameters
This function has no parameters.
Return Values
An array of all Apache response headers on success or false on failure.