How to send http requests using PHP?

Question

PHP

How to use PHP not to receive some pages, namely to send http requests and in some cases receive a response?
This needs to be implemented only with BUILT-IN tools.
For example, how to perform a slow post attack with PHP?
Another example:
There is a PHP program that should be executed indefinitely (naturally, it is repeated with delays so that the server does not die). To do this, this program must send a request to itself before terminating, but not wait for a response, since with a normal file_get_contents () request, it will not complete until it receives a response, which will heavily load the system. But it’s impossible to simply make a cycle because there are timeouts that can stop the program at the most inopportune moment (it’s better not to change timeouts, but it’s impossible to change it on hosting at all).

Answer 1

parsing-and-i.blogspot.com/2009/10/curl-post.html

Answer 2

Easy and simple
https://github.com/ARACOOOL/dHttp