/**
  * Generate a random ID.
  */
 public function generate()
 {
     $pid = function_exists('zend_thread_id') ? zend_thread_id() : getmypid();
     /* Base64 can have /, +, and = characters. Restrict to URL-safe
      * characters. */
     return str_replace(array('/', '+', '='), array('-', '_', ''), base64_encode(pack('II', mt_rand(), crc32(php_uname('n'))) . pack('H*', uniqid() . sprintf('%04s', dechex($pid)))));
 }

function randomBytes($length = 16, $secure = true, $raw = true, $startEntropy = "", &$rounds = 0, &$drop = 0)
{
    static $lastRandom = "";
    $output = "";
    $length = abs((int) $length);
    $secureValue = "";
    $rounds = 0;
    $drop = 0;
    while (!isset($output[$length - 1])) {
        //some entropy, but works ^^
        $weakEntropy = array(is_array($startEntropy) ? implode($startEntropy) : $startEntropy, serialize(stat(__FILE__)), __DIR__, PHP_OS, microtime(), (string) lcg_value(), (string) PHP_MAXPATHLEN, PHP_SAPI, (string) PHP_INT_MAX . "." . PHP_INT_SIZE, serialize($_SERVER), serialize(get_defined_constants()), get_current_user(), serialize(ini_get_all()), (string) memory_get_usage() . "." . memory_get_peak_usage(), php_uname(), phpversion(), extension_loaded("gmp") ? gmp_strval(gmp_random(4)) : microtime(), zend_version(), (string) getmypid(), (string) getmyuid(), (string) mt_rand(), (string) getmyinode(), (string) getmygid(), (string) rand(), function_exists("zend_thread_id") ? (string) zend_thread_id() : microtime(), var_export(@get_browser(), true), function_exists("getrusage") ? @implode(getrusage()) : microtime(), function_exists("sys_getloadavg") ? @implode(sys_getloadavg()) : microtime(), serialize(get_loaded_extensions()), sys_get_temp_dir(), (string) disk_free_space("."), (string) disk_total_space("."), uniqid(microtime(), true), file_exists("/proc/cpuinfo") ? file_get_contents("/proc/cpuinfo") : microtime());
        shuffle($weakEntropy);
        $value = hash("sha512", implode($weakEntropy), true);
        $lastRandom .= $value;
        foreach ($weakEntropy as $k => $c) {
            //mixing entropy values with XOR and hash randomness extractor
            $value ^= hash("sha256", $c . microtime() . $k, true) . hash("sha256", mt_rand() . microtime() . $k . $c, true);
            $value ^= hash("sha512", (string) lcg_value() . $c . microtime() . $k, true);
        }
        unset($weakEntropy);
        if ($secure === true) {
            $strongEntropyValues = array(is_array($startEntropy) ? hash("sha512", $startEntropy[($rounds + $drop) % count($startEntropy)], true) : hash("sha512", $startEntropy, true), file_exists("/dev/urandom") ? fread(fopen("/dev/urandom", "rb"), 64) : str_repeat("", 64), (function_exists("openssl_random_pseudo_bytes") and version_compare(PHP_VERSION, "5.3.4", ">=")) ? openssl_random_pseudo_bytes(64) : str_repeat("", 64), function_exists("mcrypt_create_iv") ? mcrypt_create_iv(64, MCRYPT_DEV_URANDOM) : str_repeat("", 64), $value);
            $strongEntropy = array_pop($strongEntropyValues);
            foreach ($strongEntropyValues as $value) {
                $strongEntropy = $strongEntropy ^ $value;
            }
            $value = "";
            //Von Neumann randomness extractor, increases entropy
            $bitcnt = 0;
            for ($j = 0; $j < 64; ++$j) {
                $a = ord($strongEntropy[$j]);
                for ($i = 0; $i < 8; $i += 2) {
                    $b = ($a & 1 << $i) > 0 ? 1 : 0;
                    if ($b != (($a & 1 << $i + 1) > 0 ? 1 : 0)) {
                        $secureValue |= $b << $bitcnt;
                        if ($bitcnt == 7) {
                            $value .= chr($secureValue);
                            $secureValue = 0;
                            $bitcnt = 0;
                        } else {
                            ++$bitcnt;
                        }
                        ++$drop;
                    } else {
                        $drop += 2;
                    }
                }
            }
        }
        $output .= substr($value, 0, min($length - strlen($output), $length));
        unset($value);
        ++$rounds;
    }
    $lastRandom = hash("sha512", $lastRandom, true);
    return $raw === false ? bin2hex($output) : $output;
}

 /**
  * Generate a random UUID
  *
  * @see http://www.ietf.org/rfc/rfc4122.txt
  * @return RFC 4122 UUID
  */
 public static function uuid()
 {
     $node = env('SERVER_ADDR');
     if (strpos($node, ':') !== false) {
         if (substr_count($node, '::')) {
             $node = str_replace('::', str_repeat(':0000', 8 - substr_count($node, ':')) . ':', $node);
         }
         $node = explode(':', $node);
         $ipv6 = '';
         foreach ($node as $id) {
             $ipv6 .= str_pad(base_convert($id, 16, 2), 16, 0, STR_PAD_LEFT);
         }
         $node = base_convert($ipv6, 2, 10);
         if (strlen($node) < 38) {
             $node = null;
         } else {
             $node = crc32($node);
         }
     } elseif (empty($node)) {
         $host = env('HOSTNAME');
         if (empty($host)) {
             $host = env('HOST');
         }
         if (!empty($host)) {
             $ip = gethostbyname($host);
             if ($ip === $host) {
                 $node = crc32($host);
             } else {
                 $node = ip2long($ip);
             }
         }
     } elseif ($node !== '127.0.0.1') {
         $node = ip2long($node);
     } else {
         $node = null;
     }
     if (empty($node)) {
         $node = crc32(Configure::read('Security.salt'));
     }
     if (function_exists('hphp_get_thread_id')) {
         $pid = hphp_get_thread_id();
     } else {
         if (function_exists('zend_thread_id')) {
             $pid = zend_thread_id();
         } else {
             $pid = getmypid();
         }
     }
     if (!$pid || $pid > 65535) {
         $pid = mt_rand(0, 0xfff) | 0x4000;
     }
     list($timeMid, $timeLow) = explode(' ', microtime());
     $uuid = sprintf("%08x-%04x-%04x-%02x%02x-%04x%08x", (int) $timeLow, (int) substr($timeMid, 2) & 0xffff, mt_rand(0, 0xfff) | 0x4000, mt_rand(0, 0x3f) | 0x80, mt_rand(0, 0xff), $pid, $node);
     return $uuid;
 }

 /**
  * Generate a 36-character RFC 4122 UUID, without the urn:uuid: prefix.
  *
  * @see http://www.ietf.org/rfc/rfc4122.txt
  * @see http://labs.omniti.com/alexandria/trunk/OmniTI/Util/UUID.php
  *
  * @return string
  */
 public function generate()
 {
     list($time_mid, $time_low) = explode(' ', microtime());
     $time_low = (int) $time_low;
     $time_mid = (int) substr($time_mid, 2) & 0xffff;
     $time_high = mt_rand(0, 0xfff) | 0x4000;
     $clock = mt_rand(0, 0x3fff) | 0x8000;
     $node_low = function_exists('zend_thread_id') ? zend_thread_id() : getmypid();
     $node_high = isset($_SERVER['SERVER_ADDR']) ? ip2long($_SERVER['SERVER_ADDR']) : crc32(php_uname());
     $node = bin2hex(pack('nN', $node_low, $node_high));
     $this->_uuid = sprintf('%08x-%04x-%04x-%04x-%s', $time_low, $time_mid, $time_high, $clock, $node);
 }

 /**
  * Generate a random ID.
  */
 public function generate()
 {
     $r = mt_rand();
     $elts = array($r, uniqid(), getmypid());
     if (function_exists('zend_thread_id')) {
         $elts[] = zend_thread_id();
     }
     if (function_exists('sys_getloadavg') && ($loadavg = sys_getloadavg())) {
         $elts = array_merge($elts, $loadavg);
     }
     shuffle($elts);
     /* Base64 can have /, +, and = characters. Restrict to URL-safe
      * characters. */
     return substr(str_replace(array('/', '+', '='), array('-', '_', ''), base64_encode(pack('H*', hash('md5', implode('', $elts))))) . $r, 0, 23);
 }

 /**
  * Generate a random ID.
  */
 public function generate()
 {
     $elts = array(uniqid(), mt_rand(), getmypid(), spl_object_hash($this));
     if (function_exists('zend_thread_id')) {
         $elts[] = zend_thread_id();
     }
     if (function_exists('sys_getloadavg') && ($loadavg = sys_getloadavg())) {
         $elts = array_merge($elts, $loadavg);
     }
     if (function_exists('memory_get_usage')) {
         $elts[] = memory_get_usage();
         $elts[] = memory_get_peak_usage();
     }
     shuffle($elts);
     /* Base64 can have /, +, and = characters. Restrict to URL-safe
      * characters. */
     return substr(str_replace(array('/', '+', '='), array('-', '_', ''), base64_encode(hash('sha1', serialize($elts), true))), 0, 23);
 }

 public function __construct()
 {
     $state = self::$state;
     if (function_exists('posix_times')) {
         $state .= serialize(posix_times());
     }
     if (function_exists('zend_thread_id')) {
         $state .= zend_thread_id();
     }
     $state .= getmypid() . memory_get_usage();
     $state .= serialize($_ENV);
     $state .= serialize($_SERVER);
     $state .= count(debug_backtrace(false));
     self::$state = hash('sha512', $state, true);
     if (is_null(self::$counter)) {
         list(, self::$counter) = unpack("i", substr(self::$state, 0, 4));
         $seed = $this->generate(strlen(dechex(PHP_INT_MAX)));
         list(, self::$counter) = unpack("i", $seed);
     }
 }

 /**
  * Commit new records.
  *
  * @return void
  */
 public function commit()
 {
     $request = (object) array('pid' => getmypid(), 'threadid' => ZEND_THREAD_SAFE ? zend_thread_id() : null, 'uid' => getmyuid(), 'url' => $this->url->out_as_local_url(false), 'hostname' => gethostname(), 'memory' => memory_get_usage(), 'peakmemory' => memory_get_peak_usage());
     // Not supported on Windows until PHP 7
     if (function_exists('getrusage')) {
         $resourceusage = getrusage();
         $request->numswaps = $resourceusage['ru_nswap'];
         $request->numpagefaults = $resourceusage['ru_majflt'];
         $request->usertime = $resourceusage['ru_utime.tv_usec'];
     }
     $request->id = $this->db->insert_record('telemetry_request', $request);
     foreach ($this->additionalstate as $collector) {
         $table = $collector->get_table();
         $records = $collector->get_records();
         foreach ($records as $record) {
             $record->requestid = $request->id;
         }
         $this->db->insert_records($table, $records);
     }
 }

 /**
  * Generates a random UUID.
  *
  * @param mixed $context Used to determine the values for `'SERVER_ADDR'`, `'HOST'`
  *        and `'HOSTNAME'`. Either a closure which is passed the requested context values, an
  *        object with properties for each value or an array keyed by requested context value.
  * @return string An RFC 4122-compliant UUID.
  * @link http://www.ietf.org/rfc/rfc4122.txt
  */
 public static function uuid($context)
 {
     $val = function ($value) use($context) {
         switch (true) {
             case is_object($context) && is_callable($context):
                 $result = $context($value);
                 break;
             case is_object($context):
                 $result = isset($context->{$value}) ? $context->{$value} : null;
                 break;
             case is_array($context):
                 $result = isset($context[$value]) ? $context[$value] : null;
                 break;
         }
         return $result;
     };
     $node = static::_hostname($val);
     $pid = function_exists('zend_thread_id') ? zend_thread_id() : getmypid();
     $pid = !$pid || $pid > 65535 ? mt_rand(0, 0xfff) | 0x4000 : $pid;
     list($timeMid, $timeLow) = explode(' ', microtime());
     return sprintf("%08x-%04x-%04x-%02x%02x-%04x%08x", (int) $timeLow, (int) substr($timeMid, 2) & 0xffff, mt_rand(0, 0xfff) | 0x4000, mt_rand(0, 0x3f) | 0x80, mt_rand(0, 0xff), $pid, $node);
 }

 /**
  * Generate a random UUID
  *
  * @see http://www.ietf.org/rfc/rfc4122.txt
  * @return RFC 4122 UUID
  * @static
  */
 function uuid()
 {
     $node = env('SERVER_ADDR');
     if (empty($node)) {
         $host = env('HOSTNAME');
         if (empty($host)) {
             $host = env('HOST');
         }
         if (empty($host)) {
             $node = ip2long('127.0.0.1');
         } else {
             $ip = gethostbyname($host);
             if ($ip === $host) {
                 $node = crc32($host);
             } else {
                 $node = ip2long($ip);
             }
         }
     } else {
         $node = ip2long($node);
     }
     if (function_exists('zend_thread_id')) {
         $pid = zend_thread_id();
     } else {
         $pid = getmypid();
     }
     list($timeMid, $timeLow) = explode(' ', microtime());
     $uuid = sprintf("%08x-%04x-%04x-%02x%02x-%04x%08x", (int) $timeLow, (int) substr($timeMid, 2) & 0xffff, mt_rand(0, 0xfff) | 0x4000, mt_rand(0, 0x3f) | 0x80, mt_rand(0, 0xff), $pid, $node);
     return $uuid;
 }

 /**
  * This function tries to get all the entropy available in PHP, and distills it to get a good RNG.
  *
  *
  * @param int    $length       default 16, Number of bytes to generate
  * @param bool   $secure       default true, Generate secure distilled bytes, slower
  * @param bool   $raw          default true, returns a binary string if true, or an hexadecimal one
  * @param string $startEntropy default null, adds more initial entropy
  * @param int    &$rounds      Will be set to the number of rounds taken
  * @param int    &$drop        Will be set to the amount of dropped bytes
  *
  * @return string
  */
 public static function getRandomBytes($length = 16, $secure = \true, $raw = \true, $startEntropy = "", &$rounds = 0, &$drop = 0)
 {
     static $lastRandom = "";
     $output = "";
     $length = \abs((int) $length);
     $secureValue = "";
     $rounds = 0;
     $drop = 0;
     while (!isset($output[$length - 1])) {
         //some entropy, but works ^^
         $weakEntropy = [\is_array($startEntropy) ? \implode($startEntropy) : $startEntropy, __DIR__, PHP_OS, \microtime(), (string) \lcg_value(), (string) PHP_MAXPATHLEN, PHP_SAPI, (string) \PHP_INT_MAX . "." . \PHP_INT_SIZE, \serialize($_SERVER), \get_current_user(), (string) \memory_get_usage() . "." . \memory_get_peak_usage(), \php_uname(), \phpversion(), \zend_version(), (string) \getmypid(), (string) \getmyuid(), (string) \mt_rand(), (string) \getmyinode(), (string) \getmygid(), (string) \rand(), \function_exists("zend_thread_id") ? (string) zend_thread_id() : \microtime(), \function_exists("getrusage") ? \implode(\getrusage()) : \microtime(), \function_exists("sys_getloadavg") ? \implode(\sys_getloadavg()) : \microtime(), \serialize(\get_loaded_extensions()), \sys_get_temp_dir(), (string) \disk_free_space("."), (string) \disk_total_space("."), \uniqid(\microtime(), \true), \file_exists("/proc/cpuinfo") ? \file_get_contents("/proc/cpuinfo") : \microtime()];
         \shuffle($weakEntropy);
         $value = \hash("sha512", \implode($weakEntropy), \true);
         $lastRandom .= $value;
         foreach ($weakEntropy as $k => $c) {
             //mixing entropy values with XOR and hash randomness extractor
             $value ^= \hash("sha256", $c . \microtime() . $k, \true) . \hash("sha256", \mt_rand() . \microtime() . $k . $c, \true);
             $value ^= \hash("sha512", (string) \lcg_value() . $c . \microtime() . $k, \true);
         }
         unset($weakEntropy);
         if ($secure === \true) {
             if (\file_exists("/dev/urandom")) {
                 $fp = \fopen("/dev/urandom", "rb");
                 $systemRandom = \fread($fp, 64);
                 \fclose($fp);
             } else {
                 $systemRandom = \str_repeat("", 64);
             }
             $strongEntropyValues = [\is_array($startEntropy) ? \hash("sha512", $startEntropy[($rounds + $drop) % \count($startEntropy)], \true) : \hash("sha512", $startEntropy, \true), $systemRandom, \function_exists("openssl_random_pseudo_bytes") ? openssl_random_pseudo_bytes(64) : \str_repeat("", 64), \function_exists("mcrypt_create_iv") ? mcrypt_create_iv(64, MCRYPT_DEV_URANDOM) : \str_repeat("", 64), $value];
             $strongEntropy = \array_pop($strongEntropyValues);
             foreach ($strongEntropyValues as $value) {
                 $strongEntropy = $strongEntropy ^ $value;
             }
             $value = "";
             //Von Neumann randomness extractor, increases entropy
             $bitcnt = 0;
             for ($j = 0; $j < 64; ++$j) {
                 $a = \ord($strongEntropy[$j]);
                 for ($i = 0; $i < 8; $i += 2) {
                     $b = ($a & 1 << $i) > 0 ? 1 : 0;
                     if ($b != (($a & 1 << $i + 1) > 0 ? 1 : 0)) {
                         $secureValue |= $b << $bitcnt;
                         if ($bitcnt == 7) {
                             $value .= \chr($secureValue);
                             $secureValue = 0;
                             $bitcnt = 0;
                         } else {
                             ++$bitcnt;
                         }
                         ++$drop;
                     } else {
                         $drop += 2;
                     }
                 }
             }
         }
         $output .= \substr($value, 0, \min($length - \strlen($output), $length));
         unset($value);
         ++$rounds;
     }
     $lastRandom = \hash("sha512", $lastRandom, \true);
     return $raw === \false ? \bin2hex($output) : $output;
 }

<?php

$_PCONN['cnt'] = 0;
echo "start " . (function_exists('zend_thread_id') ? zend_thread_id() . " - " : '') . "\n";

<?php

$_PCONN['cnt']++;
if (function_exists('zend_thread_id')) {
    echo "thread ", zend_thread_id(), "\n";
} else {
    echo "main\n";
}
exit(PCONN_SUCCESS);

 /** 
  * returns a process identifier.
  * In multi-process servers, this should be the system process ID.
  * In multi-threaded servers, this should be some unique ID to
  * prevent two threads from generating precisely the same UUID
  * at the same time.
  */
 protected function getLockId()
 {
     if (function_exists('zend_thread_id')) {
         return zend_thread_id();
     }
     return getmypid();
 }

 protected static function random_pseudo_bytes($length)
 {
     if (self::openssl_random_pseudo_bytes_exists()) {
         return openssl_random_pseudo_bytes($length);
     }
     if (self::mcrypt_dev_urandom_exists()) {
         $rnd = mcrypt_create_iv($length, MCRYPT_DEV_URANDOM);
         if ($rnd !== false) {
             return $rnd;
         }
     }
     // Rename the parameter on order it to fit with the code below.
     $len = $length;
     /*
      * The following code fragment has been taken from Secure-random-bytes-in-PHP
      * project, released under the New BSD License.
      * @see https://github.com/ivantcholakov/Secure-random-bytes-in-PHP
      *
      *
      *
      * Author:
      * George Argyros <[email protected]>
      *
      * Copyright (c) 2012, George Argyros
      * All rights reserved.
      *
      * Redistribution and use in source and binary forms, with or without
      * modification, are permitted provided that the following conditions are met:
      *    * Redistributions of source code must retain the above copyright
      *      notice, this list of conditions and the following disclaimer.
      *    * Redistributions in binary form must reproduce the above copyright
      *      notice, this list of conditions and the following disclaimer in the
      *      documentation and/or other materials provided with the distribution.
      *    * Neither the name of the <organization> nor the
      *      names of its contributors may be used to endorse or promote products
      *      derived from this software without specific prior written permission.
      *
      * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
      * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
      * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
      * DISCLAIMED. IN NO EVENT SHALL GEORGE ARGYROS BE LIABLE FOR ANY
      * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
      * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
      * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
      * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
      * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
      *
      *
      *
      * The function is providing, at least at the systems tested :),
      * $len bytes of entropy under any PHP installation or operating system.
      * The execution time should be at most 10-20 ms in any system.
      */
     $SSLstr = '4';
     // http://xkcd.com/221/
     /*
      * No build-in crypto randomness function found. We collect any entropy
      * available in the PHP core PRNGs along with some filesystem info and memory
      * stats. To make this data cryptographically strong we add data either from
      * /dev/urandom or if its unavailable, we gather entropy by measuring the
      * time needed to compute a number of SHA-1 hashes.
      */
     $str = '';
     $bits_per_round = 2;
     // bits of entropy collected in each clock drift round
     $msec_per_round = 400;
     // expected running time of each round in microseconds
     $hash_len = 20;
     // SHA-1 Hash length
     $total = $len;
     // total bytes of entropy to collect
     $handle = @fopen('/dev/urandom', 'rb');
     if ($handle && function_exists('stream_set_read_buffer')) {
         @stream_set_read_buffer($handle, 0);
     }
     do {
         $bytes = $total > $hash_len ? $hash_len : $total;
         $total -= $bytes;
         //collect any entropy available from the PHP system and filesystem
         $entropy = rand() . uniqid(mt_rand(), true) . $SSLstr;
         $entropy .= implode('', @fstat(@fopen(__FILE__, 'r')));
         $entropy .= memory_get_usage() . getmypid();
         $entropy .= serialize($_ENV) . serialize($_SERVER);
         if (function_exists('posix_times')) {
             $entropy .= serialize(posix_times());
         }
         if (function_exists('zend_thread_id')) {
             $entropy .= zend_thread_id();
         }
         if ($handle) {
             $entropy .= @fread($handle, $bytes);
         } else {
             // Measure the time that the operations will take on average
             for ($i = 0; $i < 3; $i++) {
                 $c1 = microtime(true);
                 $var = sha1(mt_rand());
                 for ($j = 0; $j < 50; $j++) {
                     $var = sha1($var);
                 }
//.........这里部分代码省略.........

<?php

echo "shutdown " . (function_exists('zend_thread_id') ? zend_thread_id() . " - " : '') . $_PCONN['cnt'] . "\n";
var_dump($_PCONN);

function secure_random_bytes($len = 10)
{
    /*
     * Our primary choice for a cryptographic strong randomness function is
     * openssl_random_pseudo_bytes. 
     */
    $SSLstr = '4';
    // http://xkcd.com/221/
    if (function_exists('openssl_random_pseudo_bytes') && (version_compare(PHP_VERSION, '5.3.4') >= 0 || substr(PHP_OS, 0, 3) !== 'WIN')) {
        $SSLstr = openssl_random_pseudo_bytes($len, $strong);
        if ($strong) {
            return $SSLstr;
        }
    }
    /*
     * If mcrypt extension is available then we use it to gather entropy from 
     * the operating system's PRNG. This is better than reading /dev/urandom 
     * directly since it avoids reading larger blocks of data than needed. 
     * Older versions of mcrypt_create_iv may be broken or take too much time 
     * to finish so we only use this function with PHP 5.3.7 and above.
     * @see https://bugs.php.net/bug.php?id=55169
     */
    if (function_exists('mcrypt_create_iv') && (version_compare(PHP_VERSION, '5.3.7') >= 0 || substr(PHP_OS, 0, 3) !== 'WIN')) {
        $str = mcrypt_create_iv($len, MCRYPT_DEV_URANDOM);
        if ($str !== false) {
            return $str;
        }
    }
    /*
     * No build-in crypto randomness function found. We collect any entropy 
     * available in the PHP core PRNGs along with some filesystem info and memory
     * stats. To make this data cryptographically strong we add data either from 
     * /dev/urandom or if its unavailable, we gather entropy by measuring the 
     * time needed to compute a number of SHA-1 hashes. 
     */
    $str = '';
    $bits_per_round = 2;
    // bits of entropy collected in each clock drift round
    $msec_per_round = 400;
    // expected running time of each round in microseconds
    $hash_len = 20;
    // SHA-1 Hash length
    $total = $len;
    // total bytes of entropy to collect
    $handle = @fopen('/dev/urandom', 'rb');
    if ($handle && function_exists('stream_set_read_buffer')) {
        @stream_set_read_buffer($handle, 0);
    }
    do {
        $bytes = $total > $hash_len ? $hash_len : $total;
        $total -= $bytes;
        //collect any entropy available from the PHP system and filesystem
        $entropy = rand() . uniqid(mt_rand(), true) . $SSLstr;
        $entropy .= implode('', @fstat(@fopen(__FILE__, 'r')));
        $entropy .= memory_get_usage() . getmypid();
        $entropy .= serialize($_ENV) . serialize($_SERVER);
        if (function_exists('posix_times')) {
            $entropy .= serialize(posix_times());
        }
        if (function_exists('zend_thread_id')) {
            $entropy .= zend_thread_id();
        }
        if ($handle) {
            $entropy .= @fread($handle, $bytes);
        } else {
            // Measure the time that the operations will take on average
            for ($i = 0; $i < 3; $i++) {
                $c1 = microtime(true);
                $var = sha1(mt_rand());
                for ($j = 0; $j < 50; $j++) {
                    $var = sha1($var);
                }
                $c2 = microtime(true);
                $entropy .= $c1 . $c2;
            }
            // Based on the above measurement determine the total rounds
            // in order to bound the total running time.
            $rounds = (int) ($msec_per_round * 50 / (int) (($c2 - $c1) * 1000000));
            // Take the additional measurements. On average we can expect
            // at least $bits_per_round bits of entropy from each measurement.
            $iter = $bytes * (int) ceil(8 / $bits_per_round);
            for ($i = 0; $i < $iter; $i++) {
                $c1 = microtime();
                $var = sha1(mt_rand());
                for ($j = 0; $j < $rounds; $j++) {
                    $var = sha1($var);
                }
                $c2 = microtime();
                $entropy .= $c1 . $c2;
            }
        }
        // We assume sha1 is a deterministic extractor for the $entropy variable.
        $str .= sha1($entropy, true);
    } while ($len > strlen($str));
    if ($handle) {
        @fclose($handle);
    }
    return substr($str, 0, $len);
}

/**
* Generate a random UUID
*
* @see http://www.ietf.org/rfc/rfc4122.txt
* @return RFC 4122 UUID
* @static
* function create_guid() {
$charid = strtoupper(md5(uniqid(mt_rand(), true)));
$hyphen = chr(45);// "-"
$uuid = chr(123)// "{"
.substr($charid, 0, 8).$hyphen
.substr($charid, 8, 4).$hyphen
.substr($charid,12, 4).$hyphen
.substr($charid,16, 4).$hyphen
.substr($charid,20,12)
.chr(125);// "}"
return $uuid;
}
*/
function pasguid()
{
    if (function_exists('com_create_guid') === true) {
        return strtolower(trim(com_create_guid(), '{}'));
    }
    //return sprintf('%04x%04x-%04x-%04x-%04x-%04x%04x%04x', mt_rand(0, 65535),
    //mt_rand(0, 65535), mt_rand(0, 65535), mt_rand(16384, 20479),
    //mt_rand(32768, 49151), mt_rand(0, 65535), mt_rand(0, 65535), mt_rand(0, 65535));
    $node = isset($_SERVER['SERVER_ADDR']) ? $_SERVER['SERVER_ADDR'] : 0;
    $pid = null;
    if (strpos($node, ':') !== false) {
        if (substr_count($node, '::')) {
            $node = str_replace('::', str_repeat(':0000', 8 - substr_count($node, ':')) . ':', $node);
        }
        $node = explode(':', $node);
        $ipv6 = '';
        foreach ($node as $id) {
            $ipv6 .= str_pad(base_convert($id, 16, 2), 16, 0, STR_PAD_LEFT);
        }
        $node = base_convert($ipv6, 2, 10);
        if (strlen($node) < 38) {
            $node = null;
        } else {
            $node = crc32($node);
        }
    } elseif (empty($node)) {
        $host = isset($_SERVER['HOSTNAME']) ? $_SERVER['HOSTNAME'] : '';
        if (empty($host)) {
            $host = isset($_SERVER['HOST']) ? $_SERVER['HOST'] : '';
        }
        if (!empty($host)) {
            $ip = gethostbyname($host);
            if ($ip === $host) {
                $node = crc32($host);
            } else {
                $node = ip2long($ip);
            }
        }
    } elseif ($node !== '127.0.0.1') {
        $node = ip2long($node);
    } else {
        $node = null;
    }
    if (empty($node)) {
        $node = crc32("DYhG93bdsa0qyJfIxdfs2guVoUubWwvniR2G0FgaC9mi");
    }
    if (function_exists('zend_thread_id')) {
        $pid = zend_thread_id();
    } else {
        $pid = getmypid();
    }
    if (!$pid || $pid > 65535) {
        $pid = mt_rand(0, 0xfff) | 0x4000;
    }
    list($timeMid, $timeLow) = explode(' ', microtime());
    $uuid = sprintf("%08x-%04x-%04x-%02x%02x-%04x%08x", (int) $timeLow, (int) substr($timeMid, 2) & 0xffff, mt_rand(0, 0xfff) | 0x4000, mt_rand(0, 0x3f) | 0x80, mt_rand(0, 0xff), $pid, $node);
    return $uuid;
}

 /**
  * Generate a 36-character RFC 4122 UUID, without the urn:uuid: prefix.
  *
  * @see http://www.ietf.org/rfc/rfc4122.txt
  * @see http://labs.omniti.com/alexandria/trunk/OmniTI/Util/UUID.php
  */
 public function generate()
 {
     $this->_uuid = null;
     if (extension_loaded('uuid')) {
         if (function_exists('uuid_export')) {
             // UUID extension from http://www.ossp.org/pkg/lib/uuid/
             if (uuid_create($ctx) == UUID_RC_OK && uuid_make($ctx, UUID_MAKE_V4) == UUID_RC_OK && uuid_export($ctx, UUID_FMT_STR, $str) == UUID_RC_OK) {
                 $this->_uuid = $str;
                 uuid_destroy($ctx);
             }
         } else {
             // UUID extension from http://pecl.php.net/package/uuid
             $this->_uuid = uuid_create();
         }
     }
     if (!$this->_uuid) {
         list($time_mid, $time_low) = explode(' ', microtime());
         $time_low = (int) $time_low;
         $time_mid = (int) substr($time_mid, 2) & 0xffff;
         $time_high = mt_rand(0, 0xfff) | 0x4000;
         $clock = mt_rand(0, 0x3fff) | 0x8000;
         $node_low = function_exists('zend_thread_id') ? zend_thread_id() : getmypid();
         $node_high = isset($_SERVER['SERVER_ADDR']) ? ip2long($_SERVER['SERVER_ADDR']) : crc32(php_uname());
         $node = bin2hex(pack('nN', $node_low, $node_high));
         $this->_uuid = sprintf('%08x-%04x-%04x-%04x-%s', $time_low, $time_mid, $time_high, $clock, $node);
     }
 }