Use a seguinte sintaxe
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,"http://www.example.com/process.php");
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS,$vars); //Post Fields
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$headers = [
'X-Apple-Tz: 0',
'X-Apple-Store-Front: 143444,12',
'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Accept-Encoding: gzip, deflate',
'Accept-Language: en-US,en;q=0.5',
'Cache-Control: no-cache',
'Content-Type: application/x-www-form-urlencoded; charset=utf-8',
'Host: www.example.com',
'Referer: http://www.example.com/index.php', //Your referrer address
'User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:28.0) Gecko/20100101 Firefox/28.0',
'X-MicrosoftAjax: Delta=true'
];
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
$server_output = curl_exec ($ch);
curl_close ($ch);
print $server_output ;
$vars
neste exemplo?fonte
Aqui está uma função básica:
Exemplo de uso:
fonte