Expressions And Operators: Exit

This intrinsic function terminates the current script, optionally specifying an exit value that is returned to the execution environment. For example:

exit ("Closing down\n");
exit (1);

If the exit value is a string, that string is written out. If the exit value is an integer, that represents the script's exit status code, which must be in range 0-254. Value 255 is reserved by Hack. Value 0 represents success.

exit performs the following operations, in order:

• Writes an optional string to standard output.
• Calls any functions registered via the library function register_shutdown_function in their order of registration.