PHP Manual: Shuts down a socket for receiving, sending, or both

bool socket_shutdown(Socket $socket, int $mode = 2)

The socket_shutdown function allows you to stop incoming, outgoing or all data (the default) from being sent through the socket

Note:
The associated buffer, or buffers, may or may not be emptied.

socket

A Socket instance created with socket_create.

mode

The value of mode can be one of the following:

**possible values for `mode`**
`0`	Shutdown socket reading
`1`	Shutdown socket writing
`2`	Shutdown socket reading and writing

Returns true on success or false on failure.

Version	Description
8.0.0	`socket` is a Socket instance now; previously, it was a resource.