PHP getenv('HOSTNAME')

In CLI mode getenv('HOSTNAME') r开发者_运维百科eturns HOSTNAME environment variable correctly, but when called in script returns FALSE.

Why? How can I get the HOSTNAME variable in script?

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The HOSTNAME is not available in the environment used by Apache, though it usually IS available in the environment used by the CLI.

For PHP >= 5.3.0 use this:

$hostname = gethostname();

For PHP < 5.3.0 but >= 4.2.0 use this:

$hostname = php_uname('n');

For PHP < 4.2.0 use this:

$hostname = getenv('HOSTNAME'); 
if(!$hostname) $hostname = trim(`hostname`); 
if(!$hostname) $hostname = exec('echo $HOSTNAME');
if(!$hostname) $hostname = preg_replace('#^\w+\s+(\w+).*$#', '$1', exec('uname -a')); 

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HOSTNAME is not a CGI environment variable, hence not present in normal PHP scripts.

But you can alternatively use

$hostname = `hostname`;     // exec backticks

Or read the system config file:

$hostname = file_get_contents("/etc/hostname");   // also only U*ix

But most PHP scripts should just use $_SERVER["SERVER_NAME"] or the client-requested $_SERVER["HTTP_HOST"]

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Your environment is likely cleaned in the webserver or php-fcgi/fpm start up script, so that sensitive information about the startup account is not leaked to the webserver.

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I think you want HTTP_HOST which then is empty when you access it in CLI mode.

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try something like this maybe?

function getHostName()
{
  //if we are in the shell return the env hostname
  if(array_key_exists('SHELL', $_ENV))
  {
     return getenv('HOSTNAME');
  }
  return $_SERVER['SERVER_NAME'];
}

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There also exists an ENV variable you can access via <?php print_r($_ENV); ?>. But I get the same thing: cli has more variable than the server, but it must be configuration issue.