Do I have to send data to check the PHP connection status?

Is it necessary to send data to detect the PHP connection status? I have an application. after the customer submits the computing, the server starts computing. wait for about 1 minute and return the computing result. the client exits midway through and thus needs to exit computing. Question 1: how can I check the status without sending bytes? for example, the following code checks the connection status of sending bytes: & lt ;? Functionsd help: do I have to send data to check the PHP connection status?
I have an application. after the customer submits the computing, the server starts computing. wait for about 1 minute and return the computing result. the client exits during the process and needs to exit computing.

Question 1: How to check the status without sending bytes? for example, the following code checks the connection status of sending bytes.
Function sd ()
{
If (connection_status ()! = 0)
File_put_contents ("D :\\ AppServ \\ www \\ forward and return .txt ","");
}
Register_shutdown_function ("sd ");

For ($ I = 0; $ I <10; $ I ++)
{
Echo "1 ";
Flush ();
Sleep (1 );
}
Echo "END ";
?>
This code triggers the creation of a txt file when the client closes the request, but I want to remove echo "1" or send a 0-byte message. I have tried multiple methods.



Question 2: How do proc_open programs force kill in the shutdown callback?

------ Solution --------------------
1. php only checks the connection status during output. You can output only spaces
2. if no preset communication interface is used, it is impossible to do so.
------ Solution --------------------
Proc_get_status can I kill the process id after obtaining it?