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0.26	September 30 2007
	***** Bug fixes *****
	
	Eliminated some warnings on platforms that do not implement all signals forks
	can monitor.
	
	Added boolean hook $forks::DEFER_INIT_BEGIN_REQUIRE to allow external
	modules to override forks server functions if forks loaded in a BEGIN block.
	
	***** Miscellaneous changes *****

	Added some logic in CHLD reapers for better cross-platform stability.
	
	Updated to ppport.h 3.12.

0.25	August 12 2007
	***** Bug fixes *****
	
	Updated internal PID tracking to U32 size for increased portability across
	different kernels and kernel configurations.  This corrects irregular issues
	with locks on such systems.
	
	Rewrote signal handling engine to be more portable and stable.  Changes
	eliminated behavior on BSD kernels that would cause processes to improperly
	exit with an ABRT-triggered core dump.

	***** Miscellaneous changes *****
	
	Added some protections in test suite for non-mixed fork/thread safe
	Test::More module.
	
	Added tests for new signal handling engine.

0.24	July 9 2007
	***** Threads API consistency changes *****

	Changed $thr->wantarray return value to 0-length string (was string '0') to
	meet standard wantarray scalar context return value.
	
	Added support for exit() and threads->exit() methodology and behavior.
	
	Added support for $thr->error() feature.
	
	Added a warning (and disallowing thread detach) if attempting to detach a
	thread that another thread is currently waiting to join.
	
	***** Internal behavior changes *****
	
	Added ability to swap primary process (main<->shared) that is parent of all
	processes in threaded application (via $ENV{THREADS_DAEMON_MODEL});
	should help support co-existance with some fork-aware modules, like POE.
	
	Rewrote signal handling methodology to resolve stability issues with
	inter-thread and external process signaling.
	
	Addressed the limit of 65535 shared variables: you may now create up to
	2^31-1 (2+ billion) shared variables.  Note: shared variables are currently
	not memory deallocated even if they go out of scope in all threads; thus,
	it's NOT recommended to create too many (1k+) unless you have a requirement
	to do so.  Shared var mem deallocation (when no longer referenced by any
	thread) will be addressed in a future release.
	
	Improved behavior of signal() and scope-exit unlock ordinal to insure that
	all threads, no matter what type of waiting they were performing, have an
	equal chance to receive the signal or re-acquire the lock.  The old behavior
	gave preference towards regular waiting events for signal, and timedwaiting
	events waiting to reacquire the lock for unlock ordinal.
	
	Deprecated and removed deadlock detection 'resolve_signal' feature (as this
	could not be supported in new forks.pm signal handling logic).
	
	***** Bug fixes *****
	
	Shared variable in push() on shared array now works.
	
	Eliminated slow memory leak when creating many joinable threads: the shared
	process now reclaims all shared memory allocated for joinable threads, as
	long as the application (periodically) joins then after they complete.

	Eliminated "Performing cleanup for dead thread 0" errors when compiling
	a script (i.e. perl -c script.pl).  This fix also eliminates double
	"syntax OK" reports when compiling a script.
	
	Fixed a case where detach after thread had already completed could result
	in incorrect thread group exit state reporting.
	
	Corrected a bug regarding recursive variable unlocking (was deleting
	instead of decrementing lock count).
	
	Fixed a few issues in test scripts regarding mis-reported errors related to
	older threads.pm installs or non-threaded Perl targets.
	
	Forks now starts correctly if called with 'require' or if forks::import
	is skipped for any reason.
	
	Added additional check in server to shutdown if main thread dies in a hard
	way (no notification to server or thread group).

	Added some extra protection in thread signaling (to insure that process
	exists before signaling it).
	
	Added some protection in test suite for issues with race-conditions in
	Test::More.
	
	Fixed race condition in forks07.t that could cause test to report an error.
	
	Fixed race issue in forks04.t that could cause script to error out on
	Perl instances with old native threads.pm libraries or no threads.pm
	library.
	

	***** Miscellaneous changes *****
	
	Added additional thread environment protection regarding fork occuring
	outside forks.pm module.  Also silenced a few warnings that might have
	occured in such cases.
	
	Silenced a few more unnecessary run-time warnings in specific exception
	and error cases.
	
	Rewrote END behavior for more stability and better cleanup during thread
	(process) group exit.
	
	Added internal hooks to allow external modules to override default forks.pm
	fork logic.  This should allow more flexibility to integrate forks with
	application-scope modifying environments (i.e. mod_perl, POE, Coro, etc.).
	
	Removed dependency on Reaper module.
	
	Updated version requirement for Scalar::Util module.
	
	Upgraded to ppport.h 3.11.
	
	Fixed some XS portability issues with older versions of Perl (5.8.1 and older).

0.23	8 April 2007
	***** Test suite fixes *****
	
	Corrected issue in forks04.t that would cause irrelevant but terminal
	compilation errors if real threads.pm (1.34 or later) weren't present.
	
	***** Miscellaneous changes *****
	
	Silenced a warning during external fork (non-thread) process exit. 
	
	Added some internal hooks to allow add-on modules (e.g. forks::BerkeleyDB)
	the opportunity to clean up global thread resources during shutdown.
	
0.22	19 March 2007
	***** Internal behavior changes *****

	Thread manager process now forcefully kills any still active threads
	when it exits.  This is intended to best simulate standard thread.pm
	thread cleanup during process exit.

	***** Bug fixes *****

	Corrected bug in shared server shutdown preventing complete cleanup.
	
	Corrected some platform and perl build sensitivities in the test suite.

	***** Miscellaneous changes *****

	Added additional stability against fork() outside of forks.pm.
	
	Tweaked some warnings and disabled some debug logging.
	
0.21	17 March 2007
	This revision includes *many* core changes and improvements, so be sure
	to perform full testing with existing forks-enabled applications before
	upgrading.
	
	All changes have been exposed to extensive regression testing, so you may
	expect all new features to be reasonably stable unless otherwise noted
	with a *WARNING* tag.


	***** New features *****
	
	Enabled complete thread context support.  Be sure to specify the context,
	either implicit or directly.  This also means you may not get what you
	expect if you return values in a context that doesn't match your spec.
	
	Add optional, automatic deadlock detection (warnings) in threads::shared.
	Also added is_deadlocked() method (manual deadlock detection) for threads.
	
	Added set_deadlock_option class method to forks::shared (threads::shared).

	Aware of thread params at thread creation, e.g. threads->new({}, sub {});
	
	Added complete support for $thr->wantarray and thread->wantarray.
	
	Added complete support for thread state: is_running, is_joinable,
	is_detached().
	
	Added additional support to threads->list(), with package variables:
	threads::all, threads::running, and threads::joinable.
	
	Added support for 'use forks qw(stringify)'where the TID is returned
	for a threads object in string context.
	
	Added detailed last known state of all threads on main thread exit (or
	server process unexpected exit), like:
		Perl exited with active threads:
				x running and unjoined
				y finished and unjoined
				z running and detached

	Added stubs for get_stack_size and set_stack_size, although they don't
	do anything (yet).
	
	Added support for threads->_handle and $thr->_handle, although it
	currently does not guarantee a reference to the same memory address
	each time (will be addressed in a later release).
	
	Added support for inter-thread signaling using $thr->kill('SIG...').
	*WARNING* This feature is still highly experimental and has known
	issues when sending a signal to a process sending or receiving socket
	data pertaining to a threads operation.  This will be addressed in
	a future release.
	
	Added question during build process to allow forks to override threads
	namespace if target Perl does not have native threading built in.
	Added POD describing this feature and behavior implications.
	
	
	***** Bug fixes *****

	Corrected bug in threads::shared::scalar that prevented tieing without
	a pre-existing scalar reference.
	
	Localizing $? in END block to insure that main thread exit code isn't
	accidentally overwritten during shutdown.
	
	Corrected several cases where internal auto-vivification was not intended,
	but might cause internal variable state issues.
	
	Corrected bug where fork() followed by ->isthread() in a child process
	while parent process (a thread) was already waiting on a separate thread
	could cause internal synchronization issues.
	
	Corrected bug in ->list where scalar context would return last object,
	not the number of waiting threads.

	Added additional protection in END block against external fork() occuring
	outside our knowledge causing synchronization havoc with the thread process
	group.

	Removed delete from %DETACHED on thread exit, as this property is used for
	internal thread type and state checking.
	
	Updated some error handling to suppress some undefined variable warnings.


	***** Internal behavior improvements *****

	Added silent overload of Config.pm 'useithreads' property to insure all
	modules and scripts see a true value when forks is loaded.
	
	Added explicit signal trapping of all untrapped normal and error signals
	for consistent and safe thread exit behavior.

	Added defensive error handling around non-blocking server sockets to
	protect against interruptions or busy resources during read or write.
	This should also make UNIX socket support more stable on certain target
	architectures.
	
	Added defensive logic to cleanup internal resources for threads that
	appear to have exited in an unsafe manner (and that may have left
	forks::shared resources in a unclean state) or were terminated with SIGKILL.
	
	Rewrote _length(), _send(), and _receive() internal functions to protect
	against signal interruptions, busy resources, socket disconnections, full
	socket buffers, and miscellaneous socket errors, including adding retry
	logic where appropriate.
	
	Updated _join() server function with much more intelligent logic regarding
	the state of a thread during the join process and a few more error cases
	that it needed to check for.

	threads->yield() now does a 1 ms sleep.
	
	
	***** Threads API consistency changes *****

	Can now signal unlocked variable using cond_signal and cond_broadcast.
	Note: Signaling locked returns 1; signaling unlocked returns undef.
	
	Modified lock, cond_signal, and cond_broadcast to return undef (instead
	of 1) to be consistent with threads.pm.
	
	Overloaded != for thread objects.
	
	A failed thread spawn (fork) now prints a warning and returns undef
	instead of dieing out.
	
	Detach twice on the same thread now throws an error.
	
	Improved format and content of internal warnings, and warnings now
	respect warnings state in caller for category 'threads'.
	
	Bumped threads $VERSION to 1.26, threads::shared to 1.04 to match
	version-supported features and behavior.
	
	
	*** Miscellaneous changes ***
	
	Implemented initial framework for better message handling.  This should
	help reduce overall CPU usage, and hopefully improve performance, using
	custom filter definition for request and response messages that do not
	require Storable freeze/thaw.  Requests that currently implement this 
	are: _lock and _unlock.  Responses that currently implement this are:
	any generic boolean response.
	
	Made Time::HiRes a prerequisite now.  This means that fractional
	cond_timedwait is now supported by default.
	
	Optimized sigset masking: now only one set is created at compile time
	and reused during execution.
	
	Now safely runs in taint mode when any potentially tainted environment
	vars are defined.
	
	Suppressing unnecessary warnings in the case that 'test' does not exist
	in /bin or /usr/bin.
	
	Silenced thread socket errors during thread shutdown process, unless
	debugging is enabled.
	
	Added basic blocking join poll checks, to help prevent against forever
	blocking join() cases in abnormal thread death circumstances.
	
	Thread shutdown now expects a response (to insure synchronized shutdown
	agreement with server process).
	
	General improvements in thread shutdown stability (primarily server-side).
	
0.20	5 October 2006
	Fixed rare thread start race condition where parent thread would block
	indefinitely if child thread were to spawn, complete, and exit before
	the parent could obtain the TID associated with the child thread.

	Corrected a few cases in server timedwait handling, cond_broadcast,
	and cond_signal where a lock could be prematurely transferred to
	another thread if the main thread (tid 0) were holding the lock at
	the time the event expired.
	
	Modified cond_timedwait to support fractional seconds (if Time::HiRes
	is loaded before forks).
	
	Minor changes to forks.xs for backwards compatibility with gcc 2.96.
	
	Minor cleanup in (forks.xs) bless reference handling.
	
	When using INET sockets, peer address is validated against the loopback
	address (IPv4 127.0.0.1) before accepting the connection; otherwise,
	socket is immediately closed and a warning is emitted.
	
	Added THREADS_IP_MASK env param to allow override of default IP mask
	filter.
	
	Misc cleanup of internal server environment variable handling.
	
	Moved some server code into separate subroutines.
	
0.19	21 May 2006
	Implemented an exported bless() function allow transparent bless()
	across threads with forks::shared.
	
	Implemented exported is_shared function in forks::shared.
	
	Implemented custom CHLD signal handler to cleanup zombie process.
	This change was introduced to resolve an issue on some platforms
	where using $SIG{CHLD}='IGNORE' resulted in the perl core system()
	function returning -1 instead of the exit code of the system call.
	This signal handler is only used if the target system's system() 
	call returns -1 on success when $SIG{CHLD}='IGNORE'.
	
	Added THREADS_SIGCHLD_IGNORE to allow users to force forks to use
	$SIG{CHLD}='IGNORE' on systems where a custom CHLD signal handler
	is automatically installed to support correct exit code of perl
	core system() function.
	
	Added THREADS_NICE env param to allow user to adjust forks.pm server
	process POSIX::nice value when running as root.  If unset, no change
	is made to the server process priority.  This differs from the 
	historical behavior of forks.pm defaulting to nice -19 when run as 
	root.
	
	Patched XS code to be ANSI C86 compliant (again). Code was unintentionally
	changed to require a minimum of ANSI C89 compliance since 0.17.  This
	should allow all gcc 2.95.x and other C86-compliant compilers to once
	again build forks.pm.

	Fixed prototype mismatch warning when disabling cond_wait when forks
	is not used before forks::shared.

	Added patch to quietly ignore sharing an already shared variable.
	forks::shared used to bombs out in such cases (e.g. $a:shared; share($a);).
	
	Updated to ppport.h 3.06.
	
	Implemented separate package versions for forks and threads.  threads
	package version will represent the most recent threads.pm release that
	this module is functionally compatible with.
	
	Disabled call to server process on shared variable DESTROY calls to
	decrease server communication load, as none of the affected TIE classes
	implement custom DESTROY methods.

0.18	7 December 2005
	Introduction of UNIX socket support.  Socket descriptors are written
	to /var/tmp and given rw access by all by default for best support
	on multi-user systems.

	Importing SOMAXCONN and using for socket server listener max socket
	connections (was hard coded at 10) for best (and system-level flexible)
	thread spawn stability under high load.

0.17	14 May 2005 (unreleased)
	Added method cond_timedwait and added second forms of cond_wait and
	cond_timedwait per the ithread specification (where signal var 
	differs from lock var). All elements of perl ithread interface are
	now implemented, with respect to perl 5.8.7.
	
	Added eval wrapper around new thread code execution to trap die
	events; thus, join() is now more robust (fewer chances for runtime
	hangs on '$thread->join' due to premature child thread termination).
	
	Fixed bug in _islocked in case where if main thread tried to unlock
	an already unlocked variable, it would not correctly enter if case
	and return undef or croak() due to undef value in @LOCKED resolving
	to numeric 0.

0.16	8 April 2004
	Changed semantics of debugging function: must now specify environment
	variable THREADS_DEBUG to be able to enable and disable debugging.
	If the environment variable does not exist at compile time, then all
	of the debugging code is optimised away.  So performance in production
	environments should be better than before.

	29 March 2004
	Goto &sub considered evil with regards to performance and memory
	leaking.  Therefore removed goto's where appropriate.

0.15	14 January 2004
	Just got too much mail from people attempting to use forks.pm on
	Windows.  Decided to add check for Win32 to Makefile.PL to have it
	die when attempting to run on Windows.  Added documentation to
	explain this.

0.14	7 January 2004
	Removed dependency on load.pm: it really doesn't make sense in a
	forked environment: I don't know what I was thinking in that respect.

	Added dependency on IO::Socket 1.18: we do need auto-flushing sockets
	(which seems to be pretty standard nowadays, but just to make sure).

	Fixed problem with large values / structures being passed with some
	help from Jan-Pieter Cornet at the Amsterdam PM Meeting.  Spotted by
	Paul Golds.  Added test for it.

0.13	4 January 2004
	Looked at fixing the problem with signalling unlocked variables.
	Unfortunately, there does not seem to be a quick solution.  Need to
	abandon this idea right now until I have more time.  Updated
	documentation to let the world know there is an inconsistency.

	Documented the THREADS_DEBUG environment variable and made sure it is
	unset during testing.

	Updated ppport.h to 2.009.  Didn't expect any problems with 5.8.1,
	but you never know.

0.12	2 January 2004
	Fixed problem with signalling thread 0.  Spotted by Stephen Adkins.

0.11    28 December 2003
        Added automatic required modules update using Devel::Required.

	Added requirement for Devel::Required, so that optional modules
	are listed as required on the appropriate systems.

0.10	11 November 2003
	Added check for processes dieing at the length check of a message.
	Not 100% sure whether this will be the best way to handle the main
	thread dieing, e.g. when it exits before all threads have been
	joined.

0.09	24 October 2003
	Apparently, Test::Harness cannot handle testing "threaded" scripts
	using an unthreaded Perl.  Added test for threadedness of the Perl
	being used: if so, skips testing Thread::Queue.  Spotted by several
	CPAN testers.

0.08	24 October 2003
	Shared entities that were also blessed as an object, were not
	correctly handled (ref() versus Scalar::Util::reftype() ).  Spotted
	by Jack Steadman.  Now fixed by using reftype() rather than ref().

	Dependency on Scalar::Util added (not sure when that became core).
	Added tests to excercise Thread::Queue (if available).

	10 October 2003
	Changed async() to make it a little faster by removing an extra call
	from the stack.

0.07	27 September 2003
	Added error detection in case lock or cond_xxx were called on unshared
	variables or cond_xxx were called on an unlocked variable.  Added tests
	for it in the test-suite.

	Added dummy package declaration to forks::shared.pm for CPAN's sake.
	Cleaned up the attribute handler code in forks::shared.pm a bit.

0.06	27 September 2003
	Finally grokked the documentation about attributes.  This allowed me
	to finally write the handler for the ":shared" attribute.  Which in
	the end turned out to be surprisingly simple.

	Adapted the test-suite to test usage of the ":shared" attribute as
	opposed to sharing variables with the "share" subroutine.

0.05	26 September 2003
	Increased dependency on load.pm to 0.11: versions of load.pm before
	that had issues with running under taint.

	Debug statements can now be activated by setting the environment
	variable THREADS_DEBUG to true.  As this is still experimental, this
	feature is only described in the CHANGELOG for now.

	Fixed several issues when running under taint.  Test-suite now runs
	in tainted mode just to be on the safe side.

	Removed some debug statements from the test-suite.

0.04	10 August 2003
	Implemented .xs file munging and source-filter to be able to truly
	support forks.pm under Perl 5.6.x.  Thanks to Juerd Waalboer for the
	idea of the source filter.

	It is now confirmed that forks.pm won't work under 5.005, so the
	minimum version of Perl is now set to 5.6.0 in the Makefile.PL.
	
	7 August 2003
	Tested under 5.8.1-RC4.  The WHOA! messags seem to have disappeared
	but instead a warning has appeared that cannot be suppressed.  This
	was caused by my attempt to activate the :shared attribute.  Since
	that doesn't work anyway, I removed the offending code and the
	warning went away.

	Fixed some warnings in the test-suite.

	Fixed another warning in forks.pm.  Reported by Bradley W. Langhorst.

0.03	2 April 2003
	Fixed a warning in forks.pm.  Reported by Bradley W. Langhorst.

0.02	17 January 2003
	Added dummy -package forks- to forks.pm to fool CPAN into thinking
	it really is the forks.pm module, when in fact it is of course
	threads.pm.

	Fixed some warnings in t/forks01.t.

	28 October 2002
	Made sure length packing uses Network order.

0.01	27 October 2002
	First public version of forks.pm.  Thanks to Lars Fenneberg for all
	the help so far.