PHP in a Nutshell

Name

exit()

Synopsis

    void exit ( [mixed status] )

The exit() function takes just one optional parameter and immediately terminates execution of the script. If you pass it a parameter, this is used as the script exit code. If it is a string, it is printed out. The function die() is an alias of exit() and works the same way.

Use exit() wherever you need to end a script with no further work. For example:

    if ($password != "frosties") {
            print "Access denied.";
            exit(); // note: () is optional
    }

The exit() function takes a maximum of one parameter, which can either be a program return number or a string. Many programs return numbers so that they can be chained to other programs and their output properly judged. In this case, 0 usually means "Everything went OK," and everything else means "Something went wrong." Using exit() with a string causes PHP to output the string and then terminate the script—a behavior commonly used by programmers with exit()'s alias, die(), like this:

    do_some_func() OR die("do_some_func() returned false!");

In that situation, do_some_func() will be called and, if it returns false, die() will be called to terminate the script.