This is a record of changes made to CML and the CML Library.
------------------------------------------------------------

[2020-04-08]
	Switch to using the "module subtraction" mechanism of CM so that
	the CML version of the SML/NJ Library tracks the sequential
	version automatically.  While this change breaks compatibility
	with the "Old CM", the "New CM" was introduced almost 20 years
	ago and there are many other sources of incompatibilty.

[2015-10-04]
	Tracking changes to the SML/NJ implementation of the Basis Library.

[2013-05-05]
	Added Word64 to CML Basis.  Note that, as with SML/NJ, this is not
	the LargeWord structure (because of efficiency issues).  Also added
	some missing SML Basis Library signatures to the CML version of
	the Basis.

[2012-09-24]
	Track changes to SML/NJ Library

[2011-05-10]
        Changed the paths used to specify the CML versions of libraries
        in a CM file.  The new scheme is
          $cml/basis.cm         -- the CML version of $/basis.cm
          $cml/cml.cm           -- core CML features
          $cml/cml-lib.cm       -- CML library code
          $cml/trace-cml.cm     -- TraceCML library for debugging
          $cml/smlnj-lib.cm     -- CML version of the $/smlnj-lib.cm library
          $cml/inet-lib.cm      -- CML version of the $/inet-lib.cm library
          $cml/unix-lib.cm      -- CML version of the $/unix-lib.cm library

[2011-02-18]
	Added barriers.  These are inspired by the similar mechanism in CHP,
        although we do not include any event-based operations on them as of yet.

[2010-09-16]
	Fixed the Win32 socket and polling implementation to work correctly
	with CML. Signature of poll was wrong and didn't handle sockets at all.
	(Thanks to Lars Bergstrom)

[2008-07-16]
	Fixed interface to OS.Process so that it agrees with the SML Basis Library
	(added isSuccess and sleep; status is nolonger an eqtype).

[2007-09-06]
	Exported Int64 and IntInf from basis.cm.

[2007-02-15]
	Updates to the cml-lib to track removals from the SML/NJ library.

[2007-01-28]
	Updates to the cml-lib to track additions to the SML/NJ library.

[2006-12-07]
	Carried over the fix to the SOCKET signature.

[2006-05-04]
	Fixed bug with iGetPoll, mTakePoll, and mGetPoll.  In some cases, the
	atomic region was not being closed properly.  The iGetPoll and mGetPoll
	operations just read the value field now, since there is reads are
	atomic.

[2006-02-27]
	Fixed bug with the combination of withNack and never, where the
	negative acknowledgement is never generated.  Thanks to Heath
	Putnam for the bug report and fix.

[2005-02-28]
	Fixed serious bug in structure Atom. (Must use mvar, not mailbox!)

[2005-02-24]
	Reuse signature ATOM from $/smlnj-lib.cm, thus tracking all changes.
	Implement structure Atom in terms of structure Atom in $/smlnj-lib.cm
	by protecting access to the global hashtable using an mbox lock.
	Atoms can now be created (sequentially) prior to calling RunCML.doit.

[2004-11-24]
        Made the IO implementation agnostic of size of Position.int.
        (Now compiles with either Position = Int31 or Position = Int64.)

[2003-09-23]
	Accounted for changes to socket API in Basis. (Non-blocking
	behavior is no longer a stateful property of a socket.  Instead,
	there are non-blocking versions of most functions in the
	interface.  This simplifies the CML code since it no longer
	has to do OS-specific handling of "wouldblock" etc.
	On the other hand, (trivial) CML implementations of those
	non-blocking operations had to be added.)

[2003-09-12]
        Accounted for changed type of inputLine.

[2003-09-09]
        Made CML compile under Win32 again.

[2003-09-03]
	Added *_SLICE signatures and *Slice structures (copied from
	"normal" Basis into CML Basis).
	Fixed code broken due to API changes (slices).

[2003-05-09]
	Added the missing implementation of StreamIO event constructors
	(e.g., TextIO.StreamIO.inputEvt).  Note that if you use these
	operations, then the system may not shutdown when all user threads
	are blocked.

[2003-04-21]
	The CleanUp.logMailbox function was not protected against
	interrupts (thanks to David Benson for catching this bug).

[2003-04-09]
	Changed the name of the directory cml-lib/cm to cml-lib/cm-descr
	in order to avoid a name conflict with cml-lib/CM which gets
	created by the compilation manager.  (On case-insensitive
	filesystems such as the one used by MacOS X the two names clash.)

[2003-03-10]
	Documentation cleanup.

[2002-10-01]
	Fixed a bad space leak in the stream I/O implementations.  The
	cleanup hooks were holding onto the initial buffer, which
	meant that the entire buffer chain would remain live as long
	as the stream was live.

[2001-06-20]
	Ported to SML/NJ 110.33 (in particular, the new CM).
	Under the new CM, the CML library is known as $cml/cml.cm
	and there is a CML-specific replacement for $/basis.cm
	known as $cml/basis.cm.  Two additional libraries
	($cml/cml-internal.cm and $cml/core-cml.cm) are used
	internally but should not be referred to directly by client code.
	A CML-specific replacement for $/smlnj-lib.cm is
	known as $cml-lib/smlnj-lib.cm.  The trace module is
	$cml-lib/trace-cml.cm. (The aforementioned $cml/core-cml.cm
	exists mainly to make it possible for $cml-lib/trace-cml.cm
	to refer to it.)

[2001-03-8]
	Fixed a problem in the ordering of clean-up actions.  IO streams
	were being cleaned before servers, which meant that servers could
	not use I/O in initialization or shutdown.

[2001-01-14]
	Fixed a bug in the timeout manager.  Cleanup actions were being
	executed twice, which breaks withNack.

[2000-12-12]
	Fixed a bug in the I/O manager (core-cml/io-manager.sml), where
	if there were two threads blocked on the same descriptor (one
	reading and one writing), the result might be matched to the
	wrong thread.

[2000-09-28]
	Version 1.0.13 (SML/NJ Version 110.0.7)

[2000-09-27]
	Updated the CML Library to track additions to the SML/NJ Library.

[1999-12-08]
	Fixed a collection of bugs in event.sml related to the handling of
	negative acknowledgements.

[1999-12-01]
	Modified RunCML.doit to install a dummy print hook.  This prevents
	the bug of SML/NJ's print function being called during CML execution
	(the CML print function is installed by code in TextIO, but that
	code isn't loaded by CML when the application does not specifically
	mention TextIO).

Version 1.0.12 (SML/NJ 110.0.6 and 110.8)
-----------------------------------------

[1999-09-29]
	Updated the CML Library to track additions to the SML/NJ Library.

[1999-07-05]
	Added support for Win32 sockets (thanks to Riccardo Pucella).

[1998-08-04]
	Added preliminary Win32 implementation (thanks to Riccardo Pucella).

[1998-06-01]
	Fixed type of inputLineEvt in CML_TEXT_STREAM_IO (thanks to A. Appel).

[1998-03-12]
	Fixed bug in ChanIOFn (failure to spawn threads).


Version 1.0.11 (SML/NJ 109.33 and 110)
--------------------------------------

[1997-11-21]
	Added TextIO.scanStream function.

[1997-11-21]
	Added import of PathUtil:PATH_UTIL to CML library.


Version 1.0.10 (SML/NJ 109.32)
------------------------------

[1997-09-18]
	Fixed a scheduler bug that occured when the atomicState was SignalPending
	and atomicSwitchTo was used to exit the atomic region.

[1997-09-15]
	Fixed a bug in the RunCML.doit code that prevented multiple runs (this bug
	was exposed by the previous bug fix).

[1997-09-15]
	Fixed a serious bug with the internal condition variables (Event.atomicCVarSet
	was not changing the state of the variable).

[1997-09-15]
	Introduced datatype rebinding to eliminate some structure opening.

[1997-09-14]
	Moved definition of tidToString to RepTypes, so that it can be used in
	debugging the CML internals.

[1997-09-12]
	Server initialization/shutdown is now handled by a dedicated cleanup
	routine.  Eventually, each server should define its own cleanup routine,
	and we'll get rid of logServer.

[1997-09-12]
	Fixed bugs in the initialization and shutdown protocols for the standard
	text streams.


Version 1.0.9 (SML/NJ 109.31)
-----------------------------

[1997-09-02]
	Added cleanup code for the I/O stacks (including the standard I/O streams).

[1997-08-29]
	Implemented a clean-up mechansim that is similar to that provided by
	SML/NJ.  The logging of global servers for initialization/shutdown
	is now done using cleaners, which provide somewhat finer control.
	Channel and mailbox logging is still supported, but the initialization
	is done by a dedicated cleaner.  This change is part of the overhaul
	of RunCML.

[1997-08-28]
	Qualified the use of the "cont" type constructor, which is no longer
	available at top level.

[1997-08-28]
	Replaced a few holdover uses of "abstraction" with opaque signature matching.

[1997-08-15]
	RunCML.doit now returns an OS.Process.status value.  If a CML program
	uses OS.Process.{exit,terminate} to shutdown, then the status argument
	is returned as the result.  If the system shuts down because of deadlock,
	the OS.Process.failure is returned.

[1997-08-15]
	Many changes to ensure that exportFn images do not include the entire
	top-level environment.  These include: using SMLofNJ.isolate to create
	top-level continuations, and reimplementing RunCML.exportFn to do better
	housekeeping.  To get this to work also required a number of changes
	to the SML/NJ sources.

[1997-08-15]
	Fixed bug in scheduler, where a timer interrupt in an atomic region
	was not getting marked by SignalPending.

[1997-07-24]
	The TextIO.output* functions did not implement line buffering; this
	has now been added.


Version 1.0.8 (SML/NJ 109.30)
-----------------------------

[1997-07-11]
	Changed uses of System.Unsafe to Unsafe.

[1997-07-11]
	Eliminated redefinition of Scheduler structure to avoid loss of inlining,
	since the compiler handles this properly now.

[1997-07-11]
	Added Atom.atom' (tracking SML/NJ library changes)

[1997-06-30]
	Removed Array2:ARRAY2 from library, as this is now gone from the
	SML/NJ library.


Version 1.0.7 (SML/NJ 109.29)
-----------------------------

[1997-06-11]
	Changed OS.IO.{pollErr,isErr} to OS.IO.{pollPri,isPri} (this tracks fixes
	in the SML/NJ implementation of the SML Basis Library.

[1997-06-11]
	Changes to src/Unix/posix-bin-prim-io.sml to track basis fixes.


Version 1.0.6 (SML/NJ 109.28)
-----------------------------

[1997-05-21]
	Added a temporary fix so that input operations do not cause the whole
	CML system to block waiting for input.  Eventually, there should be a
	CML version of the complete Posix API, which is the right way to avoid
	this problem.

[1997-05-21]
	Added RunCML.exportFn.
	NOTE: there are some problems with the size of exported images that
	need to be tracked down and fixed.


Version 1.0.5 (SML/NJ 109.26)
-----------------------------

[1997-03-18]
	Added SyncVar.{mSwap,mSwapEvt} operations, and changed the implementation
	of multicast channels to use it.

[1997-03-17]
	Modified SyncVar.{mGet,mGetEvt} to resume other blocked threads (just
	as iGet does).

[1997-03-16]
	Fixed a bug in SyncVar.{mTake,mTakeEvt}, where the cell was not getting
	emptied in some execution paths.

[1997-03-15]
	Added an "error thread," which is enqueued when CML is not running.
	This thread will get dispatched if someone tries to execute a CML
	operation without using RunCML.doit (not including channel allocation,
	etc.).  I also added a top-level call to Scheduler.reset, which will
	ensure that the current thread ID is initialized.

[1997-03-13]
	Fixed a serious bug in SyncVar.{iPut,mPut}, where the cell was not
	getting filled in some cases.


Version 1.0.4 (SML/NJ 109.25.2)
-------------------------------

[1997-02-28]
	Added some additional modules to the CML Library: IOUtil:IO_UTIL and
	KeywordsFn.  These were recent additions to the SML/NJ Library.  I also
	reorganized the directory structure of the CML library to make it easier
	to track changes in the SML/NJ Library.
    
[1997-02-28]
	Tracked changes in location of continuation operations changed in SML/NJ.


Version 1.0.3 (SML/NJ 109.25.1)
-------------------------------

[1997-02-25]
	Fixed bugs in the implementation of the pauseHook and schedulerHook in
	RunCMLFn (missing atomicBegin).

[1997-02-25]
	Fixed bug in implementation of TraceCML when TraceToFile was set as the
	destination.

[1997-02-18]
	Fixed bug in random access support in BinIOFn and TextIOFn (bug also in
	SML/NJ implementation).

[1997-02-17]
	Added logging/unlogging for global mailboxes.

[1997-02-17]
	Fixed bug in the TraceCML.unwatchThread.  Also changed the implementation
	to avoid potential races between unwatching a thread and its termination.

[1997-02-15]
	Various changes to the Scheduler module to improve robustness.  Added
	an exception handler around the function in enqueueTmpThread.  Replaced
	enqueueCurThread with enqueueAndSwitchCurThread, which keeps the thread
	ID bookkeeping in the same place.  And fixed a bug(?) where atomicSwitchTo
	was failing to set the current thread ID properly.

[1997-02-04]
	Added sendPoll operation on channels to CML structure.


Version 1.0.2 (SML/NJ 109.25)
-----------------------------

[1997-01-30]
	Added documentation for the Multicast and TraceCML library modules.

[1997-01-30]
	Made minor improvements to the implementation of TraceCML.

[1997-01-29]
	Changes to the SML/NJ system (available in 109.25) now make it possible
	to use the top-level print function in CML programs (it gets dynamically
	rebound to CML's version of TextIO.print when a CML program starts running).

[1997-01-27]
	Renamed CML.atEvt to CML.atTimeEvt.

[1997-01-26]
	Added SimpleRPC:SIMPLE_RPC to the CML library.

[1997-01-26]
	Fixed a bug in the I/O manager for the case when two I/O events became
	enabled for the same thread at the same time.


Version 1.0.1 (SML/NJ 109.22)
-----------------------------

[1996-11-09]
	Added UnixEnv:UNIX_ENV to the structures reexported from the CML library.

[1996-11-07]
	Fixed bug in {TextIO,BinIO}.StreamIO.endOfStream, where more m-variable
	was getting multiple puts.


Version 1.0 (SML/NJ 109.21.1)
-----------------------------

[1996-11-01]
	Added version and banner to CML structure.

[1996-11-01]
	Added CML version of Unix structure.

[1996-11-01]
	Changed the implementation of the internal condition variables to make
	them work correctly.

[1996-11-01]
	Added implementation of OS.IO.poll and OS.IO.pollEvt.

[1996-11-01]
	Fixed implementation of Socket.connect.

