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socket_shutdown

(PHP 4 >= 4.1.0, PHP 5, PHP 7, PHP 8)

socket_shutdownChiude un socket in ricezione, in invio o in entrambi i sensi

Descrizione

socket_shutdown(resource $socket, int $how = ?): bool
Avviso

Questa funzione è SPERIMENTALE. Ovvero, il comportamento di questa funzione, il nome di questa funzione, in definitiva tutto ciò che è documentato qui può cambiare nei futuri rilasci del PHP senza preavviso. Siete avvisati, l'uso di questa funzione è a vostro rischio.

La funzione socket_shutdown() permette di chiudere i trasferimenti in ingresso, in uscita o in entrambe le direzione per il socket

I valori previsti per how sono i seguenti:

possible values for how
0 Chiude il socket in lettura.
1 Chiude il socket in scrittura.
2 Chiude il socket in lettura e scrittura.

add a note

User Contributed Notes 5 notes

up
4
ludvig dot ericson at gmail dot com
18 years ago
Sockets should be first shutdown and then closed.
<?php
// Sample: Closing sockets gracefully
socket_shutdown($sock, 2);
socket_close($sock);
?>
up
2
Anonymous
1 year ago
Shutting down is a formality two peers can do before closing their connections. It's not required, but it can help assert your I/O procedures, so it's useful.

If writing is shut down, trying to send will result in a pipe error, and the remote peer will read an empty string after receiving all other pending data.

If reading is shut down, trying to receive will return an empty string, and the remote peer will get a pipe error if they try to send.

Writing should be shut down first between two peers. Remaining data should then be read and handled. If anything is sent at this point it should be a "goodbye" (nothing that requires the remote peer to write back to you). Finally, reading can be shut down.

Selection on a shut down channel will always succeed. Similarly, the remote peer will always succeed at selecting the opposite channel.
up
2
renmengyang567 at gmail dot com
4 years ago
<explain>
In this case, the TCP client is gracefully disconnected from the server

<?php

define
('BUF_SIZE',10);

// create for tcp
$sock = socket_create(AF_INET, SOCK_STREAM, getprotobyname('tcp'));
socket_bind($sock, '127.0.0.1',5200);
socket_listen($sock,1024);
$fp = fopen('./socket_shutdown.php','rb');
$clnt_sock = socket_accept($sock);

while(!
feof($fp)) {
$str = fread($fp,BUF_SIZE);
socket_write($clnt_sock,$str,BUF_SIZE);
}

$eof = "\n";
socket_write($clnt_sock,$eof,strlen($eof));

//disconnect output stream(断开输入流)
socket_shutdown($clnt_sock,1);
$ret = socket_read($clnt_sock, 100);
printf("Message from client:%s\n",$ret);
socket_close($clnt_sock);
socket_close($sock);
?>

<?php
// for tcp-client
$clnt_sock = socket_create(AF_INET, SOCK_STREAM, getprotobyname('tcp'));
socket_connect($clnt_sock, '127.0.0.1', 5200);
while ((
$cnt= @socket_read($clnt_sock, 10,PHP_NORMAL_READ)) !==false) {
file_put_contents('./receive.data',$cnt,FILE_APPEND);
}
print
"receive file data".PHP_EOL;
socket_write($clnt_sock, "Tank you");
socket_close($clnt_sock);
?>
up
1
richard dot thomas at psysolutions dot com
18 years ago
That is not a good example of a graceful shutdown. One should close the sending side of the socket and continue to read until the remote end closes its sending connection.
up
-2
recycling dot sp dot am at gmail dot com
13 years ago
Shutdown and SOL_TCP:
<?php
$a
= socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_shutdown($a, 2)
?>
PHP Warning: socket_shutdown(): unable to shutdown socket [107]: Transport endpoint is not connected

Shutdown and SOL_UDP:
<?php
$a
= socket_create(AF_INET, SOCK_STREAM, SOL_UDP);
socket_shutdown($a, 2)
?>
PHP Warning: socket_shutdown(): unable to shutdown socket [107]: Transport endpoint is not connected

Conclusion: if you are not actually connected, shutdown will fails with socket_error = 107, Transport endpoint is not connected. This is true for both TPC and UDP connection (which is suprising, UDP being a connectionless protocol). This is true no matter the value set for the how parameter.
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