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  • fsockopen()

    (PHP 4, PHP 5, PHP 7)

    打开一个网络连接或者一个Unix套接字连接

    说明

    fsockopen(string $hostname[,int $port=-1[,int &$errno[,string &$errstr[,float $timeout= ini_get("default_socket_timeout")]]]]): resource

    初始化一个套接字连接到指定主机($hostname)。

    PHP支持以下的套接字传输器类型列表所支持的套接字传输器(Socket Transports)列表。也可以通过stream_get_transports()来获取套接字传输器支持类型。

    默认情况下将以阻塞模式开启套接字连接。当然你可以通过stream_set_blocking()将它转换到非阻塞模式。

    stream_socket_client()与之非常相似,而且提供了更加丰富的参数设置,包括非阻塞模式和提供上下文的的设置。

    参数

    $hostname

    如果安装了OpenSSL,那么你也许应该在你的主机名地址前面添加访问协议ssl://或者是tls://,从而可以使用基于TCP/IP协议的SSL或者TLS的客户端连接到远程主机。

    $port

    端口号。如果对该参数传一个-1,则表示不使用端口,例如unix://

    $errno

    如果传入了该参数,holds the system level error number that occurred in the system-levelconnect()call。

    如果$errno的返回值为0,而且这个函数的返回值为FALSE,那么这表明该错误发生在套接字连接(connect())调用之前,导致连接失败的原因最大的可能是初始化套接字的时候发生了错误。

    $errstr

    错误信息将以字符串的信息返回。

    $timeout

    设置连接的时限,单位为秒。

    Note:

    注意:如果你要对建立在套接字基础上的读写操作设置操作时间设置连接时限,请使用stream_set_timeout(),fsockopen()的连接时限($timeout)的参数仅仅在套接字连接的时候生效。

    返回值

    fsockopen()将返回一个文件句柄,之后可以被其他文件类函数调用(例如:fgets(),fgetss(),fwrite(),fclose()还有feof())。如果调用失败,将返回FALSE

    错误/异常

    如果主机($hostname)不可访问,将会抛出一个警告级别(E_WARNING)的错误提示。

    更新日志

    版本说明
    4.3.0在win32系统上增加了对时限设置($timeout)参数的支持。
    4.3.0在TCP/IP协议的基础上增加了SSL和TLS。

    范例

    Example #1fsockopen()的例子

    <?php
    $fp = fsockopen("www.example.com", 80, $errno, $errstr, 30);
    if (!$fp) {
        echo "$errstr ($errno)<br />\n";
    } else {
        $out = "GET / HTTP/1.1\r\n";
        $out .= "Host: www.example.com\r\n";
        $out .= "Connection: Close\r\n\r\n";
        fwrite($fp, $out);
        while (!feof($fp)) {
            echo fgets($fp, 128);
        }
        fclose($fp);
    }
    ?>
    

    使用UDP连接

    下面这个例子展示了怎么样在自己的机器上通过UDP套接字连接(端口号13)来检索日期和时间。

    <?php
    $fp = fsockopen("udp://127.0.0.1", 13, $errno, $errstr);
    if (!$fp) {
        echo "ERROR: $errno - $errstr<br />\n";
    } else {
        fwrite($fp, "\n");
        echo fread($fp, 26);
        fclose($fp);
    }
    ?>
    

    注释

    Note:

    因为环境的不同,某些情况下在Unix套接字连接或者自定义的连接设置连接时限($timeout)可能不会生效。

    Warning

    UDP套接字有些时候在即使远程主机未知的情况,也能打开,并且不发生任何错误。只有当你通过该套接字进行读写的时候才会发现错误。之所以会这样,是因为UDP是一个“非连接状态”的协议,那么这就意味着当前操作系统直到它(套接字)真正需要发送和接受数据的时候才会去尝试为其去建立连接。

    Note:当指定数值型的 IPv6地址(例如fe80::1)时必须用方括号将 IP 围起来——例如,tcp://[fe80::1]:80

    参见

    just a quick note for users attempting https and thinking they must resort to curl or alternate methods -
    you can use fsockopen, just read the docs closely. basically they are saying to use 'ssl://' for a HTTPS (SSL) web request.
    so this would work for authorize.net, and others; even for that paypal IPN - however I think it would be best to leave the site and deal with paypal's form:
    <?php
    $host = "something.example.com";
    $port = 443;
    $path = "/the/url/path/file.php"; //or .dll, etc. for authnet, etc.
    //you will need to setup an array of fields to post with
    //then create the post string
    $formdata = array ( "x_field" => "somevalue");
    //build the post string
     foreach($formdata AS $key => $val){
      $poststring .= urlencode($key) . "=" . urlencode($val) . "&";
     }
    // strip off trailing ampersand
    $poststring = substr($poststring, 0, -1);
    $fp = fsockopen("ssl://".$host, $port, $errno, $errstr, $timeout = 30);
    if(!$fp){
     //error tell us
     echo "$errstr ($errno)\n";
      
    }else{
     //send the server request
     fputs($fp, "POST $path HTTP/1.1\r\n");
     fputs($fp, "Host: $host\r\n");
     fputs($fp, "Content-type: application/x-www-form-urlencoded\r\n");
     fputs($fp, "Content-length: ".strlen($poststring)."\r\n");
     fputs($fp, "Connection: close\r\n\r\n");
     fputs($fp, $poststring . "\r\n\r\n");
     //loop through the response from the server
     while(!feof($fp)) {
      echo fgets($fp, 4096);
     }
     //close fp - we are done with it
     fclose($fp);
    }
    ?>
    
    <?php
    // This script is an example of posting multiple files using 
    // fsockopen.
    // The tricky part is making sure the HTTP headers and file boundaries are acceptable to the target webserver.
    // This script is for example purposes only and could/should be improved upon.
    $host='targethost';
    $port=80;
    $path='/test/socket/file_upload/receive_files.php';
    // the file you want to upload 
    $file_array[0] = "dingoboy.gif"; // the file 
    $file_array[1] = "dingoboy2.gif"; // the file 
    $file_array[2] = "dingoboy3.gif"; // the file 
    $content_type = "image/gif"; // the file mime type
    //$content_type = "text/plain";
    //echo "file_array[0]:$file_array[0]<br><br>";
    srand((double)microtime()*1000000);
    $boundary = "---------------------------".substr(md5(rand(0,32000)),0,10);
    $data = "--$boundary";
    for($i=0;$i<count($file_array);$i++){
      $content_file = join("", file($file_array[$i]));
      $data.="
    Content-Disposition: form-data; name=\"file".($i+1)."\"; filename=\"$file_array[$i]\"
    Content-Type: $content_type 
    $content_file
    --$boundary";
    }
    $data.="--\r\n\r\n";
    $msg =
    "POST $path HTTP/1.0
    Content-Type: multipart/form-data; boundary=$boundary
    Content-Length: ".strlen($data)."\r\n\r\n";
    $result="";
    // open the connection
    $f = fsockopen($host, $port);
    fputs($f,$msg.$data);
    // get the response
    while (!feof($f)) $result .= fread($f,32000);
    fclose($f);
    ?>
    
    This script checks specific ports so you need to have the correct port open on the server for this to work.
    E.g if i have a windows domain controller and it is servering LDAP then the following would be used to check it is online:
    <?php
    chkServer("MyDC", "389");
    ?>
    for a webserver:
    <?php
    chkServer("MyWebSvr", "80");
    ?>
    etc etc
    --------------------------------------------------------
    <?php
    // check if a server is up by connecting to a port
    function chkServer($host, $port)
    {  
      $hostip = @gethostbyname($host); // resloves IP from Hostname returns hostname on failure
      
      if ($hostip == $host) // if the IP is not resloved
      {
        echo "Server is down or does not exist";
      }
      else
      {
        if (!$x = @fsockopen($hostip, $port, $errno, $errstr, 5)) // attempt to connect
        {
          echo "Server is down";
        }
        else 
        {
          echo "Server is up";
          if ($x)
          {
            @fclose($x); //close connection
          }
        } 
      }
    }
    ?>
    
    <?php
    /************************************************************
    * Author: Richard Lajaunie
    * Mail : richard.lajaunie@cote-azur.cci.fr
    *
    * subject : this script retreive all mac-addresses on all ports
    * of a Cisco 3548 Switch by a telnet connection
    *
    * base on the script by: xbensemhoun at t-systems dot fr
    **************************************************************/
    if ( array_key_exists(1, $argv) ){
      $cfgServer = $argv[1];
    }else{
      echo "ex: 'php test.php 10.0.0.0' \n";
      exit;
    }
    $cfgPort  = 23;        //port, 22 if SSH
    $cfgTimeOut = 10;
    $usenet = fsockopen($cfgServer, $cfgPort, $errno, $errstr), $cfgTimeOut);
    if(!$usenet){
        echo "Connexion failed\n";
        exit();
    }else{
        echo "Connected\n";
        fputs ($usenet, "password\r\n");
        fputs ($usenet, "en\r\n");
        fputs ($usenet, "password\r\n");
        fputs ($usenet, "sh mac-address-table\r\n");
        fputs ($usenet, " "); // this space bar is this for long output
       
        // this skip non essential text
        $j = 0;
        while ($j<16){
        fgets($usenet, 128);
        $j++;
        }
      stream_set_timeout($usenet, 2); // set the timeout for the fgets
      $j = 0;
        while (!feof($usenet)){
        $ret = fgets($usenet, 128);
        $ret = str_replace("\r", '', $ret);
        $ret = str_replace("\n", "", $ret);
        if (ereg("FastEthernet", $ret)){
          echo "$ret \n";
        }
        if (ereg('--More--', $ret) ){
          fputs ($usenet, " "); // for following page
        }
        $info = stream_get_meta_data($usenet);
        if ($info['timed_out']) {
          $j++;
        }
        if ($j >2){
          fputs ($usenet, "lo");
          break;
        }
      }
    }
    echo "End.\r\n";
    ?>
    
    note:
    the default protocol - if not given - seems to be tcp://
    I was tearing my hair out for a week trying to figure out how to do this.
    If you use fsockopen with a service that doesn't have an EOF, or you try to read beyond EOF or line break, PHP can hang completely.
    In my case, I was trying to write a class that talks to Kali servers (www.kali.net) to get a list of people on the chat server. To keep PHP from hanging due to the above, I discovered this:
    <?php
      class kali_utils {
        function games_list($kali_server_ip, $kali_server_port) {
          $result = array();
          $fp = fsockopen($kali_server_ip, $kali_server_port, $errno, $error, 30);
          if (!$fp) {
            $result["errno"] = $errno;
            $result["error"] = $error;
          }
          else {
            fputs($fp, "KALIQ");
            $header = fread($fp, 5);
            $bytes_left = socket_get_status($fp);
            if ($bytes_left > 0) {
              $result["results"] = fread($fp, $bytes_left["unread_bytes"]);
            }
            else {
              $result["results"] = "";
            }
            fclose($fp);
          }
          return $result;
        }
      }
    ?>
    When I send the request packet, I get a response packet of length 5. Then I call socket_get_status() and use the unread_bytes key from it to know how far to fread from the socket. Works very good.
    I've only used this on PHP 4.2.1 so far.
    I have found, when using fsockopen() and the POST method, that using HTTP/1.1 is VERY significantly slower than HTTP/1.0 (at least for the server I'm querying, an Orion-based server). Also, using cURL tended to be faster than fsockopen(), though only slightly. For example, here was a recent set of data (for the same exact request in each case):
    cURL: 4.2sec
    fsockopen() HTTP/1.0: 4.9sec
    fsockopen() HTTP/1.1: 19.9sec (!)
    I'm not sure why this was occurring. Perhaps it has something to do with the Orion server, which I have little experience with. However, it was not a fluke, and I double-checked the code to make sure there were no errors.
    EDITORS NOTE: HTTP/1.1 uses persistent connection causing this delay. Use "Connection: close" header to disable it.
    My recursive unchunk function:
    <?php
    function unchunk($result)
         {return preg_replace('/([0-9A-F]+)\r\n(.*)/sie',
                   '($cnt=@base_convert("\1", 16, 10))
                    ?substr(($str=@strtr(\'\2\', array(\'\"\'=>\'"\', \'\\\\0\'=>"\x00"))), 0, $cnt).unchunk(substr($str, $cnt+2))
                    :""
                   ',
                   $result
                   );
         }
    ?>
    
    Additional ICQ status request over proxy
    <?php
    function icq_uin($uin)
    {
      if (! is_numeric($uin))
        return false;
      $proxy_name = 'proxy.mydomain.de';
      $proxy_port = 8080;
      $proxy_user = "";
      $proxy_pass = "";
      $proxy_cont = '';
      $request_url = "http://status.icq.com/online.gif?icq=$uin";
      $proxy_fp = fsockopen($proxy_name, $proxy_port);
      if (!$proxy_fp)
        return false;
      fputs($proxy_fp, "GET $request_url HTTP/1.0\r\nHost: $proxy_name\r\n");
      fputs($proxy_fp, "Proxy-Authorization: Basic ". base64_encode ("$proxy_user:$proxy_pass")."\r\n\r\n");
      while(!feof($proxy_fp)){
        $proxy_cont .= fread($proxy_fp,4096);
      }
      fclose($proxy_fp);
      $proxy_cont = substr($proxy_cont, strpos($proxy_cont,"\r\n\r\n")+4);
      if (strstr($proxy_cont, 'online1'))
        return 'online';
      if (strstr($proxy_cont, 'online0'))
        return 'offline';
      if (strstr($proxy_cont, 'online2'))
        return 'disabled';
    }
    echo "User is ".icq_uin(123456789012345);
    ?>
    Thanx
    [EDIT BY danbrown AT php DOT net: Based on code provided in a note by (rafaelbc AT matrix DOT com DOT br) on 23-MAY-09, which has since been removed.]
    To check if a Url is Online (with http and https)
    Using @fgets to hide Warning when using SSL
    (Bug: "Warning: function.fgets SSL: fatal protocol error", http://bugs.php.net/bug.php?id=23220)
    <?php
      function isOnline($url) {
        if (!$url_info = parse_url($url)) {
          return false;  
        }
        
        switch ($url_info['scheme']) {
          case 'https':
            $scheme = 'ssl://';
            $port = 443;
            break;
          case 'http':
          default:
            $scheme = '';
            $port = 80;  
        }
        
        $data = "";
        $fid = @fsockopen($scheme . $url_info['host'], $port, $errno, $errstr, 30);
        if ($fid) {
          fputs($fid, 'HEAD ' . (isset($url_info['path'])? $url_info['path']: '/') . (isset($url_info['query'])? '?' . $url_info['query']: '') . " HTTP/1.0\r\n" . 
                "Connection: close\r\n" . 
                'Host: ' . $url_info['host'] . "\r\n\r\n");  
          while (!feof($fid)) {
            $data .= @fgets($fid, 128);
          }
          fclose($fid);
          return !empty($data);
        } else {
          return false;
        }
      } 
    ?>
    
    A simple proxy list checker. You can check a list ip:port if that port is opened on that IP.
    <?php
    $fisier = file_get_contents('proxy_list.txt'); // Read the file with the proxy list
    $linii = explode("\n", $fisier); // Get each proxy
    $fisier = fopen("bune.txt", "a"); // Here we will write the good ones
    for($i = 0; $i < count($linii) - 1; $i++) test($linii[$i]); // Test each proxy
    function test($proxy)
    {
     global $fisier;
     $splited = explode(':',$proxy); // Separate IP and port
     if($con = @fsockopen($splited[0], $splited[1], $eroare, $eroare_str, 3)) 
     {
      fwrite($fisier, $proxy . "\n"); // Check if we can connect to that IP and port
      print $proxy . '<br>'; // Show the proxy
      fclose($con); // Close the socket handle
     }
    }
    fclose($fisier); // Close the file
    ?>
    
    The following function performs pop3 authentication. Returns NULL on error, or true/false to indicate username/password matching:
    $address is the hostname of the server and $ssl is a boolean that indicates whether an SSL connection is requested.
    <?php
    function pop3authCheck($username, $password, $address, $ssl)
    {
      if ($ssl)
        $uri="ssl://$address:995";
      else
        $uri="tcp://$address:110";
      $fp=fsockopen($uri);
      if (!$fp)
        return(NULL);
      $st=fgets($fp, 512);
      if (substr($st, 0, 3)!="+OK")
      {
        fclose($fp);
        return(NULL);
      }
      $st="USER $username\n";
      if (fwrite($fp, $st)!=strlen($st))
      {
        fclose($fp);
        return(NULL);
      }
      $st=fgets($fp, 512);
      if (substr($st, 0, 3)!="+OK")
      {
        fclose($fp);
        return(NULL);
      }
      $st="PASS $password\n";
      if (fwrite($fp, $st)!=strlen($st))
      {
        fclose($fp);
        return(NULL);
      }
      $st=fgets($fp, 512);
      fclose($fp);
      if (substr($st, 0, 3)=="+OK")
        return(true);
      else if (substr($st, 0, 4)=="+ERR")
        return(false);
      else
        return(NULL);
    }
    ?>
    
    The following snippet allows you to retrieve the title of a page.
    Great for rewriting auto-url detectors to display the actual title rather then http://...
    <?php
    echo get_url_title("http://www.php.net/cal.php?id=409");
    function get_url_title($url, $timeout = 2)
    {
      $url = parse_url($url);
      if(!in_array($url['scheme'],array('','http')))
        return;
      $fp = fsockopen ($url['host'], ($url['port'] > 0 ? $url['port'] : 80), $errno, $errstr, $timeout);
      if (!$fp)
      {
        return;
        // echo "$errstr ($errno)<br>\n";
      }
      else
      {
        fputs ($fp, "GET /".$url['path'].($url['query'] ? '?'.$url['query'] : '')." HTTP/1.0\r\nHost: ".$url['host']."\r\n\r\n");
        $d = '';
        while (!feof($fp))
        {
          $d .= fgets ($fp,2048);
          if(preg_match('~(</head>|<body>|(<title>\s*(.*?)\s*</title>))~i', $d, $m))
            break;
        }
        fclose ($fp);
        return $m[3];
      }
    }
    ?>
    
    Improved HTTP/1.1 chunked transfer-encoding example.
    The sample code given below by Jack does not function correctly when run against a recent version of Apache (I'm assuming that this did once work, but from the HTTP/1.1 spec I can only assume if it did work it was based mostly on luck).
    <?php
    $header = "";
    $response = "";
    // connect
    if (!($request=fsockopen('example.com',80,$errno,$errstr))) exit($errstr);
    else {
      socket_set_timeout($request,10);
      // send request
      fwrite($request,$post);
      // get header
      do $header.=fread($request,1); while (!preg_match('/\\r\\n\\r\\n$/',$header));
      // check for chunked encoding
      if (preg_match('/Transfer\\-Encoding:\\s+chunked\\r\\n/',$header))
       do {
         $byte = "";
         $chunk_size="";
         do {
          $chunk_size.=$byte;
          $byte=fread($request,1);
         } while ($byte!="\\r");   // till we match the CR
         fread($request, 1);     // also drop off the LF
         $chunk_size=hexdec($chunk_size); // convert to real number
         $response.=fread($request,$chunk_size);
         fread($request,2);     // ditch the CRLF that trails the chunk
       } while ($chunk_size);     // till we reach the 0 length chunk (end marker)
      else {
       // check for specified content length
       if (preg_match('/Content\\-Length:\\s+([0-9]*)\\r\\n/',$header,$matches)) {
         $response=fread($request,$matches[1]);
       } else {
         // not a nice way to do it (may also result in extra CRLF which trails the real content???)
         while (!feof($request)) $response .= fread($request, 4096);
       }
      }
      // close connection
      fclose($request);
    }
    // do something useful with the response
    print($header);
    print($response);
    ?>
    Richard.
    This is a very fast program for test a form or link (many times).
    <?php
    $repeat = 100; // How many times repeat the test
    $timeout = 100; // Max time for stablish the conection
    $size  = 16;  // Bytes will be read (and display). 0 for read all
    $server = '127.0.0.1';      // IP address
    $host  = 'www.example.net';       // Domain name
    $target = '/poll/answer.asp';    // Specific program
    $referer = 'http://www.example.com/';  // Referer
    $port  = 80;
    // Setup an array of fields to get with then create the get string
    $gets = array ( 'get_field_1' => 'somevalue',
            'get_field_2' => 'somevalue' );
    // Setup an array of fields to post with then create the post string
    $posts = array ( 'post_field_1' => 'somevalue',
             'post_field_2' => 'somevalue' );
    // That's all. Now the program proccess $repeat times
    $method = "GET";
    if ( is_array( $gets ) ) {
      $getValues = '?';
      foreach( $gets AS $name => $value ){
        $getValues .= urlencode( $name ) . "=" . urlencode( $value ) . '&';
      }
      $getValues = substr( $getValues, 0, -1 );
    } else {
      $getValues = '';
    }
    if ( is_array( $posts ) ) {
      foreach( $posts AS $name => $value ){
        $postValues .= urlencode( $name ) . "=" . urlencode( $value ) . '&';
      }
      $postValues = substr( $postValues, 0, -1 );
      $method = "POST";
    } else {
      $postValues = '';
    }
    $request = "$method $target$getValues HTTP/1.1\r\n";
    $request .= "Host: $host\r\n";
    $request .= 'User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.2.1) ';
    $request .= "Gecko/20021204\r\n";
    $request .= 'Accept: text/xml,application/xml,application/xhtml+xml,';
    $request .= 'text/html;q=0.9,text/plain;q=0.8,video/x-mng,image/png,';
    $request .= "image/jpeg,image/gif;q=0.2,text/css,*/*;q=0.1\r\n";
    $request .= "Accept-Language: en-us, en;q=0.50\r\n";
    $request .= "Accept-Encoding: gzip, deflate, compress;q=0.9\r\n";
    $request .= "Accept-Charset: ISO-8859-1, utf-8;q=0.66, *;q=0.66\r\n";
    $request .= "Keep-Alive: 300\r\n";
    $request .= "Connection: keep-alive\r\n";
    $request .= "Referer: $referer\r\n";
    $request .= "Cache-Control: max-age=0\r\n";
    if ( $method == "POST" ) {
      $lenght = strlen( $postValues );
      $request .= "Content-Type: application/x-www-form-urlencoded\r\n";
      $request .= "Content-Length: $lenght\r\n";
      $request .= "\r\n";
      $request .= $postValues;
    }
    for ( $i = 0; $i < $repeat; $i++ ) {
      $socket = fsockopen( $server, $port, $errno, $errstr, $timeout );
      fputs( $socket, $request );
      if ( $size > 0 ) {
        $ret = fgets( $socket, $size );
      } else {
        $ret = '';
        while ( !feof( $socket ) ) {
          $ret .= fgets( $socket, 4096 );
        }
      }
      fclose( $socket );
      echo "<hr> $i -- $content $ret";
    }
    ?>
    Alejandro Salamanca
    thought you guys may appreciate this function, allows you to pass an array of urls to download and does so simultaneously using non-blocking sockets, then returns the data in an array.
    <?php
    // function connects to an array of URLS at the same time
    // and returns an array of results.
    function multiHTTP ($urlArr) {
     $sockets = Array(); // socket array!
     $urlInfo = Array(); // info arr
     $retDone = Array();
     $retData = Array();
     $errno  = Array();
     $errstr = Array();
     for ($x=0;$x<count($urlArr);$x++) {
     $urlInfo[$x] = parse_url($urlArr[$x]);
     $urlInfo[$x][port] = ($urlInfo[$x][port]) ? $urlInfo[$x][port] : 80;
     $urlInfo[$x][path] = ($urlInfo[$x][path]) ? $urlInfo[$x][path] : "/";
     $sockets[$x] = fsockopen($urlInfo[$x][host], $urlInfo[$x][port],
                  $errno[$x], $errstr[$x], 30);
     socket_set_blocking($sockets[$x],FALSE);
     $query = ($urlInfo[$x][query]) ? "?" . $urlInfo[$x][query] : "";
     fputs($sockets[$x],"GET " . $urlInfo[$x][path] . "$query HTTP/1.0\r\nHost: " .
        $urlInfo[$x][host] . "\r\n\r\n");
     }
     // ok read the data from each one
     $done = false;
     while (!$done) {
     for ($x=0; $x < count($urlArr);$x++) {
      if (!feof($sockets[$x])) {
      if ($retData[$x]) {
       $retData[$x] .= fgets($sockets[$x],128);
      } else {
       $retData[$x] = fgets($sockets[$x],128);
      }
      } else {
      $retDone[$x] = 1;
      }
     }
     $done = (array_sum($retDone) == count($urlArr));
     }
     return $retData;
    }
    ?>
    
    If you are using fsockopen to access webpage, but come across a redirect (Location: ) in the header and want to find and follow the redirect as in this snippet:
    <?php
    while (!feof($fp)) {
      $line=fgets($fp, 1024);        
      if (stristr($line,"location:")!="") {
      $redirect=preg_replace("/location:/i","",$line);
      }
    }
    ?>
    Then don't forget to <?php $redirect = trim($redirect); ?> before trying to follow this new link as $redirect actually has a \r\n on the end of it and won't give you a valid path in the next iteration otherwise. A six hour bug.
    Saul Dobney
    The documentation example is of a GET request. I have found POST documentation to be lacking, and here's a function to easily simulate submitting form data:
    <?php
    # $host includes host and path and filename
      # ex: "myserver.com/this/is/path/to/file.php"
    # $query is the POST query data
      # ex: "a=thisstring&number=46&string=thatstring
    # $others is any extra headers you want to send
      # ex: "Accept-Encoding: compress, gzip\r\n"
    function post($host,$query,$others=''){
      $path=explode('/',$host);
      $host=$path[0];
      unset($path[0]);
      $path='/'.(implode('/',$path));
      $post="POST $path HTTP/1.1\r\nHost: $host\r\nContent-type: application/x-www-form-urlencoded\r\n${others}User-Agent: Mozilla 4.0\r\nContent-length: ".strlen($query)."\r\nConnection: close\r\n\r\n$query";
      $h=fsockopen($host,80);
      fwrite($h,$post);
      for($a=0,$r='';!$a;){
        $b=fread($h,8192);
        $r.=$b;
        $a=(($b=='')?1:0);
      }
      fclose($h);
      return $r;
    }
    ?>
    
    The DEFAULT stream timeout is set according to default_socket_timeout in your php.ini file. Took forever for me to dig that up....
    Here is my fsockopen-based HTTP request fonction (GET and POST) :
    <?php
    function http_request(
      $verb = 'GET',       /* HTTP Request Method (GET and POST supported) */
      $ip,            /* Target IP/Hostname */
      $port = 80,        /* Target TCP port */
      $uri = '/',        /* Target URI */
      $getdata = array(),    /* HTTP GET Data ie. array('var1' => 'val1', 'var2' => 'val2') */
      $postdata = array(),    /* HTTP POST Data ie. array('var1' => 'val1', 'var2' => 'val2') */
      $cookie = array(),     /* HTTP Cookie Data ie. array('var1' => 'val1', 'var2' => 'val2') */
      $custom_headers = array(), /* Custom HTTP headers ie. array('Referer: http://localhost/ */
      $timeout = 1,      /* Socket timeout in seconds */
      $req_hdr = false,     /* Include HTTP request headers */
      $res_hdr = false      /* Include HTTP response headers */
      )
    {
      $ret = '';
      $verb = strtoupper($verb);
      $cookie_str = '';
      $getdata_str = count($getdata) ? '?' : '';
      $postdata_str = '';
      foreach ($getdata as $k => $v)
            $getdata_str .= urlencode($k) .'='. urlencode($v) . '&';
      foreach ($postdata as $k => $v)
        $postdata_str .= urlencode($k) .'='. urlencode($v) .'&';
      foreach ($cookie as $k => $v)
        $cookie_str .= urlencode($k) .'='. urlencode($v) .'; ';
      $crlf = "\r\n";
      $req = $verb .' '. $uri . $getdata_str .' HTTP/1.1' . $crlf;
      $req .= 'Host: '. $ip . $crlf;
      $req .= 'User-Agent: Mozilla/5.0 Firefox/3.6.12' . $crlf;
      $req .= 'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8' . $crlf;
      $req .= 'Accept-Language: en-us,en;q=0.5' . $crlf;
      $req .= 'Accept-Encoding: deflate' . $crlf;
      $req .= 'Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7' . $crlf;
      
      foreach ($custom_headers as $k => $v)
        $req .= $k .': '. $v . $crlf;
        
      if (!empty($cookie_str))
        $req .= 'Cookie: '. substr($cookie_str, 0, -2) . $crlf;
        
      if ($verb == 'POST' && !empty($postdata_str))
      {
        $postdata_str = substr($postdata_str, 0, -1);
        $req .= 'Content-Type: application/x-www-form-urlencoded' . $crlf;
        $req .= 'Content-Length: '. strlen($postdata_str) . $crlf . $crlf;
        $req .= $postdata_str;
      }
      else $req .= $crlf;
      
      if ($req_hdr)
        $ret .= $req;
      
      if (($fp = @fsockopen($ip, $port, $errno, $errstr)) == false)
        return "Error $errno: $errstr\n";
      
      stream_set_timeout($fp, 0, $timeout * 1000);
      
      fputs($fp, $req);
      while ($line = fgets($fp)) $ret .= $line;
      fclose($fp);
      
      if (!$res_hdr)
        $ret = substr($ret, strpos($ret, "\r\n\r\n") + 4);
      
      return $ret;
    }
    ?>
    Example usages :
    <?php
    echo http_request('GET', 'www.php.net');
    echo http_request('GET', 'www.php.net', 80, '/manual/en/function.phpinfo.php');
    echo http_request('GET', 'www.php.net', 80, '/manual/en/function.phpinfo.php', array('get1' => 'v_get1'), array(), array('cookie1' => 'v_cookie1'), array('X-My-Header' => 'My Value'));
    ?>
    [EDIT BY danbrown AT php DOT net: Contains a bugfix provided by "Wrinkled Cheese" on 24-JUN-2011 to fix the $getdata foreach() loop; another bugfix provided by Suat Secmen on 12-JAN-2012 to fix a $timeout = 1000, then stream_set_timeout($fp, 0, $timeout * 1000), equaling 1,000 seconds.]
    It appears that in PHP 5.6.0 (at least the version in Debian jessie, with openssl 1.0.1h-3), this function *is* now validating SSL certificates (in a variety of ways). First, it appears to fail for untrusted certificates (i.e. no matching CA trusted locally), and secondly, it appears to fail for mismatched hostnames in the request and certificate.
    ---------
    $ echo "<?php echo fsockopen(\"ssl://localhost\", 993); ?>" | php -a
    Interactive mode enabled
    PHP Warning: fsockopen(): Peer certificate CN=`my.test.server' did not match expected CN=`localhost' in - on line 1
    PHP Warning: fsockopen(): Failed to enable crypto in - on line 1
    PHP Warning: fsockopen(): unable to connect to ssl://localhost:993 (Unknown error) in - on line 1
    ----------
    $ echo "<?php echo fsockopen(\"ssl://my.test.server\", 993); ?>" | php -a
    Interactive mode enabled
    PHP Warning: fsockopen(): SSL operation failed with code 1. OpenSSL Error messages:
    error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed in - on line 1
    PHP Warning: fsockopen(): Failed to enable crypto in - on line 1
    PHP Warning: fsockopen(): unable to connect to ssl://my.test.server:993 (Unknown error) in - on line 1
    ---------
    #installed CA locally
    ---------
    $ echo "<?php echo fsockopen(\"ssl://my.test.server\", 993); ?>" | php -a
    Interactive mode enabled
    Resource id #1
    Here's a function to just fetch the contents behind an URL.
    <?php
    function fetchURL( $url ) {
      $url_parsed = parse_url($url);
      $host = $url_parsed["host"];
      $port = $url_parsed["port"];
      if ($port==0)
        $port = 80;
      $path = $url_parsed["path"];
      if ($url_parsed["query"] != "")
        $path .= "?".$url_parsed["query"];
      $out = "GET $path HTTP/1.0\r\nHost: $host\r\n\r\n";
      $fp = fsockopen($host, $port, $errno, $errstr, 30);
      fwrite($fp, $out);
      $body = false;
      while (!feof($fp)) {
        $s = fgets($fp, 1024);
        if ( $body )
          $in .= $s;
        if ( $s == "\r\n" )
          $body = true;
      }
      
      fclose($fp);
      
      return $in;
    }
    ?>
    
    Trying to fsockopen an ssl:// connection, but it was hanging for a long time, ignoring timeout parameter, and eventually returning false, without an error message. 
    Turns out (at least) on Windows it validates certificates and doesn't have a valid certificate store.
    This worked for me:
    - download Mozilla's certificate store from https://curl.haxx.se/ca/cacert.pem
    - copy it inside php installation (for example: c:\php)
    - and set it up in php.ini 
        
           openssl.cafile="c:\php\cacert.pem"
    My system: Apache/2.4.29 (Win64) OpenSSL/1.0.2n PHP/5.6.38
    <?php
    /*
    this script i used for remote my PvPGN Server, to check email user.
    not good, but it work.
    */
    set_time_limit(0); 
    $host  = 'host';
    $port  = 'port';
    $user  = 'user';
    $pass  = 'pass';
    $socket = fsockopen($host, $port) or die('Could not connect to: '.$host);
    $userdota = "palma";
    if($socket) 
    { 
      sendcmd("\r",$socket);
      $status = "open"; // set status open
        
      while($status=="open") //while we are connected to the server 
       {   
           $line = @fgets($socket, 1024) ;
           /////////////login////////////////  
          if (strstr($line, "there is no guest account"))
           {
             sendcmd($user."\r\n",$socket);
             sendcmd($pass."\r\n",$socket);
           }  
          //////////////send command ////////////////////
          if (strstr($line,"Your unique name: ".$user))
           { sendcmd("/finger ".$userdota."\r\n",$socket);
           }
          
          //////////////get email////////////////////
          if (strstr($line,"email:")) // if respone server write "email:"
           { 
             $pattern = '/email:(.*) ,/';
             preg_match($pattern, $line, $matches);
             fclose($socket); 
             $status="close"; // status close
             $matches=str_replace(" ","", $matches);
             $matches=str_replace(",is_operator:0,is_admin:0,","", $matches);
             $matches=str_replace("email:","", $matches);
             print $matches[0];         
             $email=$matches[0];
           }
          if (strstr($line,"ERROR: Invalid user.")) // if respone server write "ERROR: Invalid user."
           { 
             
             fclose($socket); 
             $status="close";
             $error ="Invalid User";  // error message
           }
          
          ////////////login failed //////////////////////////       
          if (strstr($line, "Login failed")) // if respone server write "Login failed"
           {
             $error = "Login Failed";  // error message
             fclose($socket); 
             $status="close";
           }
          
          flush(); // close
       
       }
         
    }
    function sendcmd($cmd,$socket) // send command function
    {
     fputs($socket, $cmd, strlen($cmd)); 
    }
    ?>
    
    For some reason the default FreeBSD 7.0 port (jailed environment) breaks fsockopen() on SSL URLs, returning a constant stream of nothing! In my case this resulted in php-cgi bringing down lighttpd completely, in rapid time! Avoid FreeBSD/jails/fsockopen + SSL. Use curl_init() instead.
    When downloading large files, it is not really efficient to put the whole server answer in memory before parsing the data to remove the header parts. Here is a simple way to do it while writing the data as it arrive:
    <?php
    // $socket is a valid fsockopen handle
    $out = '';
    $headerendfound = false;
    $fp = fopen($fileTarget, 'w');
    $buffer = '';
    while (!feof($socket)) {
      $out = fgets ($socket,16384);
      if ($headerendfound) {
        fwrite($fp, $out);
        print '.';
      }
      if (!$headerendfound) {
        $buffer .= $out;
        print "searching for header\n";
        $headerend = strpos($buffer, "\r\n\r\n");
        if ($headerend !== false) {
          $headerendfound = true;
          fwrite($fp, substr($buffer, $headerend+4));
          $buffer = '';
        }
      }
    } 
    fclose($fp);
    fclose($socket);
    ?>
    
    My $0.02 on handling chunked transfer encoded output... Has rudimentary error handling.
    <?php
    //
    // Example usage...
    //
    $server = '127.0.0.1';
    $port  = '80';
    $uri   = '/cgi-bin/random-cgi';
    $content = 'Your post content...';
    $post_results = httpPost($server,$port,$uri,$content);
    if (!is_string($post_results)) {
      die('uh oh, something went wrong');
      } else {
      die('Here are your results: ' . $post_results);
      }
    //
    // Post provided content to an http server and optionally
    // convert chunk encoded results. Returns false on errors,
    // result of post on success. This example only handles http,
    // not https.
    //
    function httpPost($ip=null,$port=80,$uri=null,$content=null) {
      if (empty($ip))     { return false; }
      if (!is_numeric($port)) { return false; }
      if (empty($uri))    { return false; }
      if (empty($content))  { return false; }
      // generate headers in array.
      $t  = array();
      $t[] = 'POST ' . $uri . ' HTTP/1.1';
      $t[] = 'Content-Type: text/html';
      $t[] = 'Host: ' . $ip . ':' . $port;
      $t[] = 'Content-Length: ' . strlen($content);
      $t[] = 'Connection: close';
      $t  = implode("\r\n",$t) . "\r\n\r\n" . $content;
      //
      // Open socket, provide error report vars and timeout of 10
      // seconds.
      //
      $fp = @fsockopen($ip,$port,$errno,$errstr,10);
      // If we don't have a stream resource, abort.
      if (!(get_resource_type($fp) == 'stream')) { return false; }
      //
      // Send headers and content.
      //
      if (!fwrite($fp,$t)) {
        fclose($fp);
        return false;
        }
      //
      // Read all of response into $rsp and close the socket.
      //
      $rsp = '';
      while(!feof($fp)) { $rsp .= fgets($fp,8192); }
      fclose($fp);
      //
      // Call parseHttpResponse() to return the results.
      //
      return parseHttpResponse($rsp);
      }
    //
    // Accepts provided http content, checks for a valid http response,
    // unchunks if needed, returns http content without headers on
    // success, false on any errors.
    //
    function parseHttpResponse($content=null) {
      if (empty($content)) { return false; }
      // split into array, headers and content.
      $hunks = explode("\r\n\r\n",trim($content));
      if (!is_array($hunks) or count($hunks) < 2) {
        return false;
        }
      $header = $hunks[count($hunks) - 2];
      $body  = $hunks[count($hunks) - 1];
      $headers = explode("\n",$header);
      unset($hunks);
      unset($header);
      if (!verifyHttpResponse($headers)) { return false; }
      if (in_array('Transfer-Encoding: chunked',$headers)) {
        return trim(unchunkHttpResponse($body));
        } else {
        return trim($body);
        }
      }
    //
    // Validate http responses by checking header. Expects array of
    // headers as argument. Returns boolean.
    //
    function validateHttpResponse($headers=null) {
      if (!is_array($headers) or count($headers) < 1) { return false; }
      switch(trim(strtolower($headers[0]))) {
        case 'http/1.0 100 ok':
        case 'http/1.0 200 ok':
        case 'http/1.1 100 ok':
        case 'http/1.1 200 ok':
          return true;
        break;
        }
      return false;
      }
    //
    // Unchunk http content. Returns unchunked content on success,
    // false on any errors... Borrows from code posted above by
    // jbr at ya-right dot com.
    //
    function unchunkHttpResponse($str=null) {
      if (!is_string($str) or strlen($str) < 1) { return false; }
      $eol = "\r\n";
      $add = strlen($eol);
      $tmp = $str;
      $str = '';
      do {
        $tmp = ltrim($tmp);
        $pos = strpos($tmp, $eol);
        if ($pos === false) { return false; }
        $len = hexdec(substr($tmp,0,$pos));
        if (!is_numeric($len) or $len < 0) { return false; }
        $str .= substr($tmp, ($pos + $add), $len);
        $tmp = substr($tmp, ($len + $pos + $add));
        $check = trim($tmp);
        } while(!empty($check));
      unset($tmp);
      return $str;
      }
    ?>
    
    If you have to use a proxy to make requests outside of your local network, you may use this class:
    <?php
    /*
     * 
     * No Proxy Authentification Implemented; PHP 5
     * 
     */
    class RemoteFopenViaProxy {
      private $result;
      private $proxy_name;
      private $proxy_port;
      private $request_url;
      public function get_proxy_name() {
        return $this->proxy_name;
      }
      public function set_proxy_name($n) {
        $this->proxy_name = $n;
      }
      public function get_proxy_port() {
        return $this->proxy_port;
      }
      public function set_proxy_port($p) {
        $this->proxy_port = $p;
      }
      public function get_request_url() {
        return $this->request_url;
      }
      public function set_request_url($u) {
        $this->request_url = $u;
      }
      public function get_result() {
        return $this->result;
      }
      public function set_result($r) {
        $this->result = $r;
      }
      private function get_url_via_proxy() {
        $proxy_fp = fsockopen($this->get_proxy_name(), $this->get_proxy_port());
        if (!$proxy_fp) {
          return false;
        }
        fputs($proxy_fp, "GET " . $this->get_request_url() . " HTTP/1.0\r\nHost: " . $this->get_proxy_name() . "\r\n\r\n");
        while (!feof($proxy_fp)) {
          $proxy_cont .= fread($proxy_fp, 4096);
        }
        fclose($proxy_fp);
        $proxy_cont = substr($proxy_cont, strpos($proxy_cont, "\r\n\r\n") + 4);
        return $proxy_cont;
      }
      private function get_url($url) {
        $fd = @ file($url);
        if ($fd) {
          return $fd;
        } else {
          return false;
        }
      }
      private function logger($line, $file) {
        $fd = fopen($file . ".log", "a+");
        fwrite($fd, date("Ymd G:i:s") . " - " . $file . " - " . $line . "\n");
        fclose($fd);
      }
      function __construct($url, $proxy_name = "", $proxy_port = "") {
        $this->set_request_url($url);
        $this->set_proxy_name($proxy_name);
        $this->set_proxy_port($proxy_port);
      }
      public function request_via_proxy() {
        $this->set_result($this->get_url_via_proxy());
        if (!$this->get_result()) {
          $this->logger("FAILED: get_url_via_proxy(" . $this->get_proxy_name() . "," . $this->get_proxy_port() . "," . $this->get_request_url() . ")", "RemoteFopenViaProxyClass.log");
        }
      }
      public function request_without_proxy() {
        $this->set_result($this->get_url($this->get_request_url()));
        if (!$this->get_result()) {
          $this->logger("FAILED: get_url(" . $url . ")", "RemoteFopenViaProxyClass.log");
        }
      }
    }
    ?>
    Use it this way:
    <?php
    // call constructor
    $obj = new RemoteFopenViaProxy($insert_request_url, $insert_proxy_name, $insert_proxy_port);
    // change settings after object generation
    $obj->set_proxy_name($insert_proxy_name);
    $obj->set_proxy_port($insert_proxy_port);
    $obj->set_request_url($insert_request_url);
    $obj->request_via_proxy();
    echo $obj->get_result();
    ?>
    If there are errors during execution, the script tries to write some useful information into a log file.
    <?php
    // Check for new version
      $current_version = explode('.', '1.0.00');
      $minor_revision = (int) $current_version[2];
      $errno = 0;
      $errstr = $version_info = '';
      if ($fsock = fsockopen("www.exanmple.eu", 80, $errno, $errstr, 30))
      {
        @fputs($fsock, "GET /ver.txt HTTP/1.1\r\n");
        @fputs($fsock, "HOST: www.example.eu\r\n");
        @fputs($fsock, "Connection: close\r\n\r\n");
        $get_info = false;
        while (!@feof($fsock))
        {
          if ($get_info)
          {
            $version_info .= @fread($fsock, 1024);
          }
          else
          {
            if (@fgets($fsock, 1024) == "\r\n")
            {
              $get_info = true;
            }
          }
        }
        @fclose($fsock);
        $version_info = explode("\n", $version_info);
        $latest_head_revision = (int) $version_info[0];
        $latest_minor_revision = (int) $version_info[2];
        $latest_version = (int) $version_info[0] . '.' . (int) $version_info[1] . '.' . (int) $version_info[2];
        if ($latest_head_revision == 2 && $minor_revision == $latest_minor_revision)
        {
          $version_info = '<p style="color:green">OK</p>';
        }
        else
        {
          $version_info = '<p style="color:red">neaktualne';
          $version_info .= '<br />'Latest_version_info' . $latest_version) . ' ' . sprintf(Current_version_info'. '1.0.00') . '</p>';
        }
      }
      else
      {
        if ($errstr)
        {
          $version_info = '<p style="color:red">' . sprintf(Connect_socket_error) . '</p>';
        }
        else
        {
          $version_info = '<p>'Socket_functions_disabled'</p>';
        }
      }
      
      $version_info .= '<p>'Mailing_list_subscribe_reminder'</p>';
    echo $version_info;
    ?>
    
    PHP (or OpenSSL) may not always choose to use e.g. TLS 1.2, but you can force it to with tlsv1.2://
    https://docs.php.net/manual/en/migration56.openssl.php#migration56.openssl.crypto-method
    This was a great help to me, given Twitter's recent API changes to require TLS 1.2+.
    I was having trouble doing an https in fopen and with fsockopen where the address had ssl://. I was getting error code 114 in the log. After much research i found that there was some ssl conflict trouble with MySQL 5.0.20-5.0.33. It had some functions that were interfering with openssl that showed up in the php install.
    http://bugs.mysql.com/bug.php?id=21930
    http://bugs.mysql.com/bug.php?id=19289
    Lots of tries and lots of reading http-headers...
    If you want to post $_POST vars and (in this case) one file named userfile to $remote_server and $remote_url.
    <?php
        // get the necessary data
        $file_name = $_FILES['userfile']['name'];   // the file
        $tmp_name = $_FILES['userfile']['tmp_name'];   // the file
        $content_type = $_FILES['userfile']['type'];   // the file mime type
        
        srand((double)microtime()*1000000);
        $boundary = "---------------------".substr(md5(rand(0,32000)),0,10);
        
        // Build the header
        $header = "POST $remote_url HTTP/1.0\r\n";
        $header .= "Host: $remote_server\r\n";
        $header .= "Content-type: multipart/form-data, boundary=$boundary\r\n";
        // attach post vars
        foreach($_POST AS $index => $value){
          $data .="--$boundary\r\n";
          $data .= "Content-Disposition: form-data; name=\"".$index."\"\r\n";
          $data .= "\r\n".$value."\r\n";
          $data .="--$boundary\r\n";
        }
        // and attach the file
        $data .= "--$boundary\r\n";
        $content_file = join("", file($tmp_name));
        $data .="Content-Disposition: form-data; name=\"userfile\"; filename=\"$file_name\"\r\n";
        $data .= "Content-Type: $content_type\r\n\r\n";
        $data .= "".$content_file."\r\n";
        $data .="--$boundary--\r\n";
        $header .= "Content-length: " . strlen($data) . "\r\n\r\n";
             // Open the connection
        $fp = fsockopen($remote_server, 80);
        // then just 
        fputs($fp, $header.$data);
        fclose($fp);
    ?>
    
    on my FreeBSD vm, with Joomla, I was getting the error 
    fsockopen(): unable to connect to ssl://localhost:443 (Unknown error)
    when using a contact form and also the module updating process.
    After reading other notes on here, regarding certificate validation, I installed the port ca_root_nss
    (Root certificates from certificate authorities included in the Mozilla
    NSS library and thus in Firefox and Thunderbird.)
    Now it works
    Here is a function for testing a website/URI for availability:
    <?php
      /*
      * @return boolean
      * @param string $link
      * @desc  berprft die angegeben URL auf Erreichbarkeit (HTTP-Code: 200)
      */
      function url_validate( $link )
      {    
        $url_parts = @parse_url( $link );
        if ( empty( $url_parts["host"] ) ) return( false );
        if ( !empty( $url_parts["path"] ) )
        {
          $documentpath = $url_parts["path"];
        }
        else
        {
          $documentpath = "/";
        }
        if ( !empty( $url_parts["query"] ) )
        {
          $documentpath .= "?" . $url_parts["query"];
        }
        $host = $url_parts["host"];
        $port = $url_parts["port"];
        // Now (HTTP-)GET $documentpath at $host";
        if (empty( $port ) ) $port = "80";
        $socket = @fsockopen( $host, $port, $errno, $errstr, 30 );
        if (!$socket)
        {
          return(false);
        }
        else
        {
          fwrite ($socket, "HEAD ".$documentpath." HTTP/1.0\r\nHost: $host\r\n\r\n");
          $http_response = fgets( $socket, 22 );
          
          if ( ereg("200 OK", $http_response, $regs ) )
          {
            return(true);
            fclose( $socket );
          } else
          {
    //        echo "HTTP-Response: $http_response<br>";
            return(false);
          }
        }
      }
    ?>
    
    Try this.
    Use AUTH when necessary.
    Read RFC 821 when having problems.
    <?php
      $handle = smtp_connect($smtp_server, 25, 30, 1, 1, 1);
      echo smtp_command($handle, "EHLO $domain\r\n", 1, 1);
      echo smtp_command($handle, "MAIL FROM:<$from_mail>\r\n", 1, 1);
      echo smtp_command($handle, "RCPT TO:<$to_mail>\r\n", 1, 1);
      echo smtp_command($handle, "DATA\r\n", 1, 1);
      echo smtp_command($handle, "$message\r\n.\r\n", 1, 1);
      // don't do it like this - it will hang up
      // echo smtp_command($handle, "$message", 1, 1);
      // echo smtp_command($handle, "\r\n.\r\n", 1, 1);
      echo smtp_command($handle, "QUIT\r\n", 1, 1);
      smtp_close($handle); 
      
      
      function smtp_connect($host, $port, $timeout=30, $echo_command=False, $echo_response=False, $nl2br=False)
      {
        $errno = 0;
        $errstr = 0;
        if($echo_command)
        {
          if($nl2br) { echo nl2br("CONNECTING TO $host\r\n"); }
          else { echo "CONNECTING TO $host\r\n"; }
        }
        $handle = fsockopen($host, $port, $errno, $errstr, $timeout);
        if(!$handle)
        {
          if($echo_command)
          {
            if($nl2br) { echo nl2br("CONNECTION FAILED\r\n"); }
            else { echo "CONNECTION FAILED\r\n"; }
          }
          return False;
        }
        if($echo_command)
        {
          if($nl2br) { echo nl2br("SUCCESS\r\n"); }
          else { echo "SUCCESS\r\n"; }
        }
        $response = fgets($handle,1);
        $bytes_left = socket_get_status($handle);
        if ($bytes_left > 0) { $response .= fread($handle, $bytes_left["unread_bytes"]); }
        if($echo_response)
        {
          if($nl2br) { echo nl2br($response); }
          else { echo $response; }
        }
        return $handle;
      }
      function smtp_command($handle, $command, $echo_command=False, $nl2br=False)
      {
        if($echo_command)
        {
          if($nl2br) { echo nl2br($command); }
          else { echo $command; }
        }
        fputs($handle, $command);
        $response = fgets($handle,1);
        $bytes_left = socket_get_status($handle);
        if ($bytes_left > 0) { $response .= fread($handle, $bytes_left["unread_bytes"]); }
        if($nl2br) { return nl2br($response); }
        else { return $response; }
      }
      
      function smtp_close($handle)
      {
        fclose($handle);
      }
    ?>
    
    To make a telnet connection with a Cisco router:
    <?php
    $cfgServer = "nnn.nnn.nnn.nnn"; //IP of your router
    $cfgPort  = 23;        //port, 22 if SSH
    $cfgTimeOut = 10;
    $usenet = fsockopen($cfgServer, $cfgPort, $errno, $errstr, $cfgTimeOut);
    if(!$usenet)
        {
        echo "Connexion failed\n";
        exit();
        }
    else
        {
        echo "Connected\n<BR>";
        fputs ($usenet, "toto\r\n");
        fputs ($usenet, "en\r\n");
        fputs ($usenet, "tutu\r\n");
        fputs ($usenet, "exit\r\n");
        while (!feof($usenet))
            {
            echo ". ".fgets($usenet, 128)."<BR>\n";
            }
        }
    ?>
    Then you will have:
    Connected
    . \1\3\x18\x1f
    .
    . User Access Verification
    .
    . Password:
    . testXB>en
    . Password:
    . testXB#exit
    .
    Here's a quick function to establish a connection to a web server that will time out if the connection is lost after a user definable amount of time or if the server can't be reached.
    Also supports Basic authentication if a username/password is specified. Any improvements or criticisms, please email me! :-)
    Returns either a resource ID, an error code or 0 if the server can't be reached at all. Returns -1 in the event that something really wierd happens like a non-standard http response or something. Hope it helps someone.
    Cheers,
    Ben Blazely
    <?php
    function connectToURL($addr, $port, $path, $user="", $pass="", $timeout="30")
    {
     $urlHandle = fsockopen($addr, $port, $errno, $errstr, $timeout);
     if ($urlHandle)
     {
     socket_set_timeout($urlHandle, $timeout);
     if ($path)
     {
      $urlString = "GET $path HTTP/1.0\r\nHost: $addr\r\nConnection: Keep-Alive\r\nUser-Agent: MyURLGrabber\r\n";
      if ($user)
      $urlString .= "Authorization: Basic ".base64_encode("$user:$pass")."\r\n";
      $urlString .= "\r\n";
      fputs($urlHandle, $urlString);
      $response = fgets($urlHandle);
      if (substr_count($response, "200 OK") > 0)   // Check the status of the link
      {
       $endHeader = false;           // Strip initial header information
       while ( !$endHeader)
       {
       if (fgets($urlHandle) == "\r\n")
        $endHeader = true;
       }
       return $urlHandle;           // All OK, return the file handle
      }
      else if (strlen($response) < 15)        // Cope with wierd non standard responses
      {
       fclose($urlHandle);
       return -1;
      }
      else                      // Cope with a standard error response
      {
       fclose($urlHandle);
       return substr($response,9,3);
      }
      }
      return $urlHandle;
     }
     else
     {
      return 0;
     }
     }
    }
    ?>
    
    Here is how to connect to the web from behind a proxy server:
    <?php
    /*************start code**************/
    /*your proxy server address*/
    $proxy = "192.168.10.1";
    /*your proxy server port*/
    $port = 8080;
    /*the url you want to connect to*/
    $url = "http://www.php.net/";
    $fp = fsockopen($proxy, $port);
    fputs($fp, "GET $url HTTP/1.0\r\nHost: $proxy\r\n\r\n");
    while(!feof($fp)){
     $line = fgets($fp, 4000);
     print($line);
    }
    fclose($fp);
    /**************end code**************/
    ?>
    
    Here is some code to help out abit more with the EOF problem.
    I had a problem where I needed to strip out so many lines of server input to get back right data i wanted.
    <?php
    $port=4000;
    $host="localhost";
    $message="test";
    $status=senddata($host,$port,$message);
    print "$status";
    function senddata($host,$port,$message) {
    #takes in account servers that do not return EOF character
    #send data to server and get back input
    #function globals
    $linenumber="2"; #amount of lines to get rid of before we give input
    $lineamount="1"; #amount of lines to read after we give input
    $fp = fsockopen("$host", $port, $errno, $errstr, 30);
    if (!$fp) {
      echo "$errstr ($errno)";
    }
    else {
      for ($i = 1; $i < $linenumber+1; $i++) {
       fread ($fp,1);
       $bytes_left = socket_get_status($fp);
       if ($bytes_left > 0) { fread($fp, $bytes_left[unread_bytes]); }
      }
      fputs($fp, "$message\r\n");
      for ($i = 1; $i < $lineamount+1; $i++) {
       $status.=fread($fp,1);
       $bytes_left = socket_get_status($fp);
       if ($bytes_left > 0) { $status.=fread($fp, $bytes_left[unread_bytes]); }
      }
      fclose ($fp);
    }
    return $status;
    }
    ?>
    
    Here's how to send an email using SMTP. This includes rudimentary checking on server responses during the process of sending an email. Could be improved by more comprehensive processing of the result codes...or going on to the next mail exchanger when you fail after connecting to the first.
    <?php
    function another_mail($to,$subject,$headers,$message)
    {
     // Could get this from the php ini?
     $from="me@example.com";
     list($me,$mydomain) = split("@",$from);
     // Now look up the mail exchangers for the recipient
     list($user,$domain) = split("@",$to,2);
     if(getmxrr($domain,$mx,$weight) == 0) return FALSE;
     // Try them in order of lowest weight first
     array_multisort($mx,$weight);
     $success=0;
     foreach($mx as $host) {
     // Open an SMTP connection
     $connection = fsockopen ($host, 25, $errno, $errstr, 1);
     if (!$connection)
      continue;
     $res=fgets($connection,256);
     if(substr($res,0,3) != "220") break;
     // Introduce ourselves
     fputs($connection, "HELO $mydomain\n");
     $res=fgets($connection,256);
     if(substr($res,0,3) != "250") break;
     // Envelope from
     fputs($connection, "MAIL FROM: $from\n");
     $res=fgets($connection,256);
     if(substr($res,0,3) != "250") break;
     // Envelope to
     fputs($connection, "RCPT TO: $to\n");
     $res=fgets($connection,256);
     if(substr($res,0,3) != "250") break;
     // The message
     fputs($connection, "DATA\n");
     $res=fgets($connection,256);
     if(substr($res,0,3) != "354") break;
     // Send To:, From:, Subject:, other headers, blank line, message, and finish
     // with a period on its own line.
     fputs($connection, "To: $to\nFrom: $from\nSubject: $subject\n$headers\n\n$message\n.\n");
     $res=fgets($connection,256);
     if(substr($res,0,3) != "250") break;
     // Say bye bye
     fputs($connection,"QUIT\n");
     $res=fgets($connection,256);
     if(substr($res,0,3) != "221") break;
     // It worked! So break out of the loop which tries all the mail exchangers.
     $success=1;
     break;
     }
     // Debug for if we fall over - uncomment as desired
     // print $success?"Mail sent":"Failure: $res\n";
     if($connection) {
     if($success==0) fputs($connection, "QUIT\n");
     fclose ($connection);
     }
     return $success?TRUE:FALSE;
    }
    another_mail("recipient@example.com","My Subject","X-mailer: PHP Script\nX-another-header: Whatever","Test email body.\n\nNote if you actually put a period on a line\nby itself, the function will terminate prematurely.\n\nYou will get a partial email sent though.\n");
    ?>
    
    Did you know that fsockopen() DOES NOT validate SSL certificates whatsoever? For the sake of World's overall security level, I guess it would be a very positive idea to add a BIG WARNING notice on the manual page!
    Citing the extensive study titled "The Most Dangerous Code in the World: Validating SSL Certificates in Non-Browser Software" published in 2012 (google it if they removed the link) on page 5:
    "PHP provides several methods for establishing SSL connections. For example, fsockopen, which opens a raw socket to the remote server, can be used to connect to SSL servers by putting “ssl://” in the URL. Even though fsockopen does not perform any certificate checks whatsoever, PHP application developers routinely use it for SSL connection establishment (see Section 9)."
    For proper certificate validation with some level of ease, you can always move to cURL, but be careful:
    "PHP also provides a cURL binding, which uses cURL’s default settings to establish SSL connections with proper certificate validation. As we show in Sections 7.1, 7.2, and 7.3, application developers often set cURL options incorrectly, overriding the defaults and breaking certificate validation."
    For more detailed insights, try out the following code:
    <?php readfile("http".str_replace('+', '.', implode('/', array(":", null, "www+cs+utexas+edu", "~shmat", "shmat_ccs12.pdf")))); ?>
    
    Set up SSL connection to server that requires client certificate:
    Convert client certificate from *.pfx (pkcs12) into*.pem with openssl (if needed):
    > openssl pkcs12 -in keys.pfx -out keys.pem
    PHP:
    <?php
    $context = stream_context_create();
    $result = stream_context_set_option($context, 'ssl', 'local_cert', '/path/to/keys.pem');
    $result = stream_context_set_option($context, 'ssl', 'passphrase', 'pass_to_access_keys');
    $socket = fsockopen('ssl://'.$host, 443, $errno, $errstr, 30, $context);
    ?>
    

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