I want to check if a site is alive within this cURL code?

I use this code to get a response/result from the other server and I want to know how can I check if the site is alive?

$ch = curl_init('http://domain.com/curl.php');
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $dat开发者_Python百科a);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$result = curl_exec($ch);
curl_close($ch);
if (!$result)
// it will execute some codes if there is no result echoed from curl.php

All you really have to do is a HEAD request to see if you get a 200 OK message after redirects. You do not need to do a full body request for this. In fact, you simply shouldn't.

function check_alive($url, $timeout = 10) {
  $ch = curl_init($url);

  // Set request options
  curl_setopt_array($ch, array(
    CURLOPT_FOLLOWLOCATION => true,
    CURLOPT_NOBODY => true,
    CURLOPT_TIMEOUT => $timeout,
    CURLOPT_USERAGENT => "page-check/1.0" 
  ));

  // Execute request
  curl_exec($ch);

  // Check if an error occurred
  if(curl_errno($ch)) {
    curl_close($ch);
    return false;
  }

  // Get HTTP response code
  $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
  curl_close($ch);

  // Page is alive if 200 OK is received
  return $code === 200;
}

here is the simpler one

<?php
$yourUR="http://sitez.com";

$handles = curl_init($yourUR);
curl_setopt($handles, CURLOPT_NOBODY, true);
curl_exec($handles);
$resultat = curl_getinfo($handles, CURLINFO_HTTP_CODE);

echo $resultat;
?>

Check a web url status by PHP/cURL function :

Condition is , If HTTP status is not 200 or 302, or the requests takes longer than 10 seconds, so the website is unreachable...

<?php
/**
 *
 * @param string $url URL that must be checked
 */

function url_test( $url ) {
    $timeout = 10;
    $ch = curl_init();
    curl_setopt ( $ch, CURLOPT_URL, $url );
    curl_setopt ( $ch, CURLOPT_RETURNTRANSFER, 1 );
    curl_setopt ( $ch, CURLOPT_TIMEOUT, $timeout );
    $http_respond = curl_exec($ch);
    $http_respond = trim( strip_tags( $http_respond ) );
    $http_code = curl_getinfo( $ch, CURLINFO_HTTP_CODE );
    if ( ( $http_code == 200 ) || ( $http_code == 302 ) ) {
        return true;
    } else {
        // you can return $http_code here if necessary or wanted
        return false;
    }
    curl_close( $ch );
}

// simple usage:
$website = "www.example.com";
if( !url_test( $website ) ) {
    echo $website ." is down!";
} else {
    echo $website ." functions correctly.";
}
?>

You can try with cURL:

curl -I "<URL>" 2>&1 | awk '/HTTP\// {print $2}'

It will return 200 when it's alive

Keep it short and simple...

$string = @file_get_contents('http://domain.com/curl.php');

If $string is null or empty the page is probably unreachable (or actually doesnt output anything).