It halts the compiler execution

Example

<?php
__halt_compiler();
?>

It returns the capabilities of the user’s browser

Example

<?php
echo “<pre>”;
print_r( get_browser(null,true));
?>

It output a message and terminate the current script

Example

<?php
$fp = fopen($site,”r”) or exit(“Failed”);
?>

Output

phpcode

It evaluates a string as PHP code.

Example

<?php
$lan = “phpcode”;
$text = ‘$lan’;
eval(“$value = “$text”;”);
echo $value;
?>

Output

phpcode

Its an  alias of the exit() and prints a message and exits the current script

Example

<?php
$fp  =   fopen(“test.xml”,”r”) or die(“Failed”);
?>

It checks whether a given named constant exists

Example

<?php
echo defined(“LAN”)?LAN:”Not defined”;
?>

Output

Not defined

It defines a constant

Example

<?php
define(“LAN”,”phpcode”);
echo constant(“LAN”);
?>

Output

phpcode

It returns the value of a constant

Example

<?php
define(“LAN”,”phpcode”);
echo constant(“LAN”);
?>

Output

phpcode

It checks if the script timed out

Example

<?php
if(connection_timeout())
echo “Timed out”;
?>

Its deprecated in PHP 4.0.5

It returns the current connection status

Example

<?php
echo connection_status ();
?>

It returns one of the follows

0 – CONNECTION_NORMAL – connection is running normally
1 – CONNECTION_ABORTED – connection is aborted by user or network error
2 – CONNECTION_TIMEOUT –  connection timed out
3 – CONNECTION_ABORTED & CONNECTION_TIMEOUT