PHP 8.0.26 Released!

socket_write

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

socket_write向套接字写数据

说明

socket_write(Socket $socket, string $data, ?int $length = null): int|false

函数 socket_write()socket 写入 data

参数

socket

data

要写入到缓冲区的数据。

length

可选参数 length 可以指定写入 socket 的字节长度。如果写入的字节长度大于缓冲区长度,默认将被截取为缓冲区长度。

返回值

返回成功写入 socket 的字节数 或者在失败时返回 false。可以通过调用 socket_last_error() 来检索实际的错误码。将错误码作为参数传递给 socket_strerror() 以获得错误的文本解释。

注意:

对于 socket_wirte() 来说返回 0 是完全有效的,这代表没有字节被写入。如果发生错误,务必使用 === 运算符来判断是否为 false

更新日志

版本 说明
8.0.0 现在 socketSocket 实例, 之前是 resource
8.0.0 length 现在允许为 null。

注释

注意:

socket_write() 不一定会写入缓冲区全部的内容。根据网络缓冲区的条件,即使缓冲区待写入的数据很多,也可能只写入一部分,甚至是一个字节。因此,必须注意是否所有数据都写入成功。

参见

add a note

User Contributed Notes 8 notes

up
8
revelable at hotmail dot com
11 years ago
Here we have the same function to write a socket but with improved performance.

If the messager are not larger, they will be written entirely with a single socket_write() call. And is not needed to call the substr() function for the first bucle.

<?php
$st
="Message to sent";
$length = strlen($st);
       
    while (
true) {
       
       
$sent = socket_write($socket, $st, $length);
           
        if (
$sent === false) {
       
            break;
        }
           
       
// Check if the entire message has been sented
       
if ($sent < $length) {
               
           
// If not sent the entire message.
            // Get the part of the message that has not yet been sented as message
           
$st = substr($st, $sent);
               
           
// Get the length of the not sented part
           
$length -= $sent;

        } else {
           
            break;
        }
           
    }
?>
up
2
anonymous
1 year ago
sending a few mbs or more results in incomplete transfers, send data in a loop and chunks instead, socket_write reports complete write even though it is only a partial transfer, possibly because of buffer overrun somewhere.

$strlen=strlen($msg);
$totaltransferred=0;

$blocksize=10000;
for ($a=0;$a<$strlen;$a+=$blocksize){
    $part=substr($msg,$a,$blocksize);
    $transferred=socket_write($socket,$part,strlen($part));
    $totaltransferred+=$transferred;
}
   
if ($totaltransferred<$strlen){
    echo "incomplete transfer";
}
up
1
php at deguest dot asia
7 years ago
I often read in php docs users not checking for the php function returned value, and in the case of socket_write, I could not see here in the comment anyone botering to read on the socket the server reply.
Then one user thought it would be a good idea to use usleep after a socket_write on a smtp connection.
Actually, if you check the server reply, not only will it give time for the server to reply before you write again on the socket, but also this is a great opportunity to check what the server replied you.
For instance, for smtp connection :
In this example MAIL_SERVER, MAIL_PORT and DEBUG are constants I defined.
<?php
function sendmail( $param )
{
   
$from    = &$param[ 'from' ];
   
$to      = &$param[ 'to' ];
   
$message = &$param[ 'data' ];
   
   
$isError = function( $string )
    {
        if(
preg_match( '/^((\d)(\d{2}))/', $string, $matches ) )
        {
            if(
$matches[ 2 ] == 4 || $matches[ 2 ] == 5 ) return( $matches[ 1 ] );
        }
        else
        {
            return(
false );
        }
    };
   
    try
    {
       
$socket = null;
        if( (
$socket = socket_create( AF_INET, SOCK_STREAM, SOL_TCP ) ) == false )
        {
            throw new
Exception( sprintf( "Unable to create a socket: %s", socket_strerror( socket_last_error() ) ) );
        }
        if( !
socket_connect( $socket, MAIL_SERVER, MAIL_PORT ) )
        {
            throw new
Exception( sprintf( "Unable to connect to server %s: %s", MAIL_SERVER, socket_strerror( socket_last_error() ) ) );
        }
       
$read = socket_read( $socket, 1024 );
        if(
$read == false )
        {
            throw new
Exception( sprintf( "Unable to read from socket: %s", socket_strerror( socket_last_error() ) ) );
        }
       
        if(
socket_write( $socket, sprintf( "HELO %s\r\n", gethostname() ) ) === false )
        {
            throw new
Exception( sprintf( "Unable to write to socket: %s", socket_strerror( socket_last_error() ) ) );
        }
       
$read = socket_read( $socket, 1024 );
        if(
$read == false )
        {
            throw new
Exception( sprintf( "Unable to read from socket: %s", socket_strerror( socket_last_error() ) ) );
        }
        else
        {
            if( (
$errCode = $isError( $read ) ) ) throw new Exception( "Server responded with an error code $errCode" );
        }
       
        if(
socket_write( $socket, sprintf( "MAIL FROM: %s\r\n", $from ) ) === false )
        {
            throw new
Exception( sprintf( "Unable to write to socket: %s", socket_strerror( socket_last_error() ) ) );
        }
       
$read = socket_read( $socket, 1024 );
        if(
$read == false )
        {
            throw new
Exception( sprintf( "Unable to read from socket: %s", socket_strerror( socket_last_error() ) ) );
        }
        else
        {
            if( (
$errCode = $isError( $read ) ) ) throw new Exception( "Server responded with an error code $errCode" );
        }
       
/* And some more code, but not enough place in comment */
       
return( $totalWriten );
    }
    catch(
Exception $e )
    {
       
$ERROR = sprintf( "Error sending mail message at line %d. ", $e->getLine() ) . $e->getMessage();
        return(
false );
    }
}
up
1
gtk at linux dot online dot no
20 years ago
from http://www.manualy.sk/sock-faq/unix-socket-faq-2.html
read() is equivalent to recv() with a flags parameter of 0. Other values for the flags parameter change the behaviour of recv(). Similarly, write() is equivalent to send() with flags == 0.
up
-3
webmaster at you-are-infected dot com
16 years ago
If you connect to a Server in a way like you do with telnet or some similar protokoll you may have problems with sending data to the server. I found out that at some servers there is a different between:

<?php
   
    socket_write
($my_socket, $line, strlen ($line));
   
socket_write ($my_socket, "\r\n", strlen ("\r\n"));
   
?>
witch worked at least, and
<?php
    socket_write
($my_socket, $line."\r\n", strlen ($line."\r\n"));
?>
wich made the server stop sending any data.

I hope this helps to save a lot of time. I needed about two days to find out, that this was the problem ;)
up
-5
jean at briskula dot si
11 years ago
Some clients (Flash's XMLSocket for example) won't fire a read event until a new line is recieved.

<?php
   
/*
     * Write to a socket
     * add a newline and null character at the end
     * some clients don't read until new line is recieved
     *
     * try to send the rest of the data if it gets truncated
     */
   
function write(&$sock,$msg) {
       
$msg = "$msg\n\0";
       
$length = strlen($msg);
        while(
true) {
           
$sent = socket_write($sock,$msg,$length);
            if(
$sent === false) {
                return
false;
            }
            if(
$sent < $length) {
               
$msg = substr($msg, $sent);
               
$length -= $sent;
                print(
"Message truncated: Resending: $msg");
            } else {
                return
true;
            }
        }
        return
false;
    }
?>
up
-6
masterwaster at gmail dot com
14 years ago
Hi,
if you got same problems like i have

<?php
@socket_write($xd, "Good Bye!\n\r");
@
socket_shutdown($xd, 2);
@
socket_close($xd);
?>

wont'tx send "Good Bye!\n\r" to the opened socket.

but if you put a
usleep or something like echo "";
between write and shutdown its working.
up
-8
divinity76 at gmail dot com
7 years ago
function AddTCPChecksum(&$data){
//feel free to add some error handling for strlen($data)>65535...
$data=pack("v",strlen($data)).$data;
}
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