osx man page for attrs

attrs(3pm)						 Perl Programmers Reference Guide						attrs(3pm)

NAME
       attrs - set/get attributes of a subroutine (deprecated)

SYNOPSIS
	   sub foo {
	       use attrs qw(locked method);
	       ...
	   }

	   @a = attrs::get(&foo);

DESCRIPTION
       NOTE: Use of this pragma is deprecated.	Use the syntax

	   sub foo : locked method { }

       to declare attributes instead.  See also attributes.

       This pragma lets you set and get attributes for subroutines.  Setting attributes takes place at compile time; trying to set invalid
       attribute names causes a compile-time error. Calling "attrs::get" on a subroutine reference or name returns its list of attribute names.
       Notice that "attrs::get" is not exported.  Valid attributes are as follows.

       method
	   Indicates that the invoking subroutine is a method.

       locked
	   Setting this attribute is only meaningful when the subroutine or method is to be called by multiple threads. When set on a method
	   subroutine (i.e. one marked with the method attribute above), perl ensures that any invocation of it implicitly locks its first
	   argument before execution. When set on a non-method subroutine, perl ensures that a lock is taken on the subroutine itself before
	   execution. The semantics of the lock are exactly those of one explicitly taken with the "lock" operator immediately after the
	   subroutine is entered.

perl v5.10.0							    2007-12-18								attrs(3pm)