Hi,

Could you provide a reproducible test case?

I had a look into this and tried to recreate with the following script:

<?php

$s1 = stream_socket_server('127.0.0.1:8501');
$s2 = stream_socket_server('127.0.0.1:8502');

$conn1 = stream_socket_accept($s1);
$conn2 = stream_socket_accept($s2);

$pid = pcntl_fork();

if ($pid > 0) {
    $read = [$conn1, $conn2];
    $write = $except = null;
    var_dump(stream_select($read, $write, $except, 10));
    sleep(1);
    fwrite($conn1, "parent test conn 1\n");
    fwrite($conn2, "parent test conn 2\n");
    fclose($conn1);
    fclose($conn2);
    echo "Parent ends\n";
} else {
    sleep(1);
    fwrite($conn1, "child test conn 1\n");
    fwrite($conn2, "child test conn 2\n");
    fclose($conn1);
    fclose($conn2);
    echo "Child ends\n";
}


Then I tested that in nc and all worked as expected. It means getting either

Child ends
int(0)
Parent ends

conn1 received:
child test conn 1
parent test conn 1

and conn2 received:
child test conn 2
parent test conn 2

It also worked if I wrote something in one of the child connection. Then the parent result was 
Child ends
int(1)
Parent ends

It means that closing connection in child does not impact in any way the parent connectiont which is expected and works like in C which also matches my expectations when looking to the code.

I think we need the already requested test case for this. I will close this bug with "No Feedback" but feel free to open a new GitHub issue if you still experience the problem. As noted a test script will be required.