Light OPC Server development library
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RELEASE HISTORY


(the last 4 digits in version number are month & day)

Year 2003:

[v0.888-0313] 
Compatible with fresh OPC headers.

[v0.887-0303] ***BUGFIX***
Memory corruption bug fixed in lo_variant_changetype_array().
This function is not used by lightopc itself but provided for
applications. It was introdused in v0.88.
Crash may occure when this function used to convert from 
complex types such as VT_ARRAY|VT_BSTR, VT_ARRAY|VT_UNKNOWN etc.

Changed logic fixing the W2k timing problem.


[v0.886-0219] 
Source archive v0.886-0217 was broken.

[v0.886-0217] (2003)
Conditions of *ldSubscribe() callback can be altered.
See lightopc.h for loDF_SUBSCRIBE_RAW.


Year 2002:

[v0.885-1227] 
Support for COM aggregation has been included.
See lightopc.h for loClientCreate_agg().

The SAMPLE.cpp cleaned up a bit.

Makefile.MSVC now compatible with both VS6 and VS7 (DOT-net).


[v0.884-0930] ***BUGFIX***
Crash on changing quality of a zero-lenght BSTR.

[v0.883-0819] ***BUGFIX***
In versions 0.86 to 0.882 function loCreateService() can be 
executed only once: Second call will hang. This bug doesn't affect 
applications those didn't call loCreateService() more than once
since server process / dll loaded.

[v0.882-0808]
The function loCacheTimestamp() has been introduced for event-driven tags. 
It does support multiple groups of tags sharing the same timestams.


[v0.881-0717]
The IOPCServer::RemoveGroup() method does not longer 
invoke CoDisconnectObject() unless bForce=1 specified.

[v0.88-0621]
GMEM_flags have been changed. Previous implementation of 
	in-proc AsyncIO1 may go wrong with some clients.
V0.87 specefic bug in loOP_STOP implementation has been fixed.
The lo_variant_change_array() has been introduced.


[v0.87-0518]
Minor changes. No bugfix.

[v0.87-0516]
Significant faster tag creation.
A few functions have been renamed:
        loRegisterServer        loServerRegister
        loUnregisterServer      loServerUnregister
        loLastTrid              loTridLast
        loWaitTrid              loTridWait
The functions loTridOrder() and
lo_variant_to_filetime(), lo_filetime_to_variant() have been introduced.
We have added workaround for a minor W2k specific timing problem.
        (Under some circumance granularity of Sleep()/WaitFor...() might
        became less than granularity of system clock. see LO_TIMEBACK for
        details).
The Pthreads now supported (though, native sychronization is still better).


[v0.86-0414]
Bug in implementation of loDW_ALLDONE has been fixed.
The all allocated enumerators now can be disconnected
via loSetState() (in earlier versions only servers & groups could
be disconnected this way).

[v0.85-0404]
Bug in apartment model support (loDf_BOTHMODEL) has been fixed.
Minor changes in interface of loSetState().

[v0.84-0328]
A bug in loRegisterServer() has been fixed.
Fixed OnDataChange callback generation for fresh added/activated
items (in earlier versions a new item has not been included in
OnDataChange until loCacheUpdate() occured).

[v0.82-0311]
Minor corrections for Win95/98.
Interfaces has been changed:
		- ldAskItemID();
		- ldReadTags();
		- ldWriteTags().

[v0.8-0211] (2002)
Tuned to MINGW32/gcc.
Improved sample.
Minor change in loClientChain().


Year 2001:

[v0.7-1227]
Enhanced support for ItemProperties.

[v0.6-1108]
Bug in GroupEnumerator has been fixed.

[v0.6-1101]
Improved support for large amounts of tags.

[v0.6-0928]
per-group localization now supported.
Example of the localized enumerated tag is included.

[v0.5-0918]
Cosmetic changes in interface.
Bug on writing to arrays has fixed.

[v0.4-0629]
ItemProperties now is supported.
Bugs with SetDatatypes & Group browsing are fixed.
Improved support for interrupt - driven tags.
(The timestamps for all not changed tags can be updated
 at once without even providing the tag list).

[v0.3-0426]
The logger accepts symbolyc names of levels.
The sample now contains the code for log redirections and
runtime reconfigurations.

The "both" threading model now is supported. Althrough we suggested
not to use it when possible. Threading behavior of the server can
be tuned by compile-time options LO_USE_FREEMARSH/LO_USE_BOTHMODEL
as well as by run-time options loDf_FREEMARSH/loDf_BOTHMODEL.

[v0.2] 8 March 2001
Initial release.
No AsyncIO except data change subscription.

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