This function is an alias for apache_request_headers(). Please read the apache_request_headers() documentation for more information on how this function works.
so if you want to use this function in any platform,you should detect if it is exists:
if (!function_exists(‘getallheaders‘))
{
function getallheaders()
{
$headers = ‘‘;
foreach ($_SERVER as $name => $value)
{
if (substr($name, 0, 5) == ‘HTTP_‘)
{
$headers[str_replace(‘ ‘, ‘-‘, ucwords(strtolower(str_replace(‘_‘, ‘ ‘, substr($name, 5)))))] = $value;
}
}
return $headers;
}
}
php getallheaders使用注意事项,布布扣,bubuko.com
原文：http://www.cnblogs.com/libmw/p/3794157.html