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Tcl/Tk 8.6b3 Release Announcement
September 18, 2012

The Tcl Core Team is pleased to announce the 8.6b3 releases of the Tcl
dynamic language and the Tk toolkit.  This is the third beta release
of Tcl/Tk 8.6.  More details can be found below.  We would like to
express our gratitude to all those who submit bug reports and patches.
This information is invaluable in enabling us to identify and eliminate
problems in the core.

Where to get the new releases:

Tcl/Tk 8.6b3 sources are freely available as open source from the
Tcl Developer Xchange web site at:

This web page also contains additional information about the releases,
including new features and notes about installing and compiling the
releases.  Sources are always available from the Tcl SourceForge
project's file distribution area:

Binaries for most major platforms are available from:

For additional information:

Please visit the Tcl Developer Xchange web site:

This site contains a variety of information about Tcl/Tk in general, the
core Tcl and Tk distributions, Tcl development tools, and much more.

Summary of Changes since Tcl/Tk 8.6b2:

The following were the main changes in Tcl/Tk 8.6b3.  A complete list
can be found in the changes file at the root of the source tree.  The
more complete ChangeLog is also included with each source release.

This is a beta release of 8.6.  The beta designation means that the
feature set for 8.6 is believed to be complete, and the focus is now
on testing and bug fixing moving quickly toward an 8.6.0 release.
All relevant bug fixes (and some more) up to and including 8.5.12 changes
are included in 8.6b3.  This release is a development release, and should
only be considered for deployment use after considerable testing.

    * [TIP 388] New syntax for extended Unicode: \Uhhhhhhhh

    * [TIP 396] New command: [yieldto]

    * [TIP 398] Non-blocking channels no longer forced to flush on exit

    * [TIP 380] New OO builtin class: [oo::Slot]

    * [TIP 397] New OO standard method: <cloned> - extends [oo::copy]

    * [TIP 395] New subcommand: [string is entier]

    * [TIP 403] Redefined color names to match Web colors.

    * On Windows, adopt convention that Ctrl-A means Select-All

    * Increased use of virtual events in Tk.

    * [TIP 376] Bundled distribution of sqlite3 3.7.14, tdbcsqlite3-1.0b17

    * Update to Unicode 6.2 support.

    * Bytecode compiled: [catch] [dict with] [lrange] [lreplace]

    * Updated packages:
	- dde 1.4.0b1
		[TIP 106] New option: [dde execute|poke -binary]
	- http 2.8.4
		Accept IPv6 URLs;  Make -headers override -type.
	- Itcl 4.0b8
	- msgcat 1.5.0
		[TIP 404] New commands: [mcflset] [mcflmset]
	- registry 1.3.0
		fix [registry keys] failure
	- tcltest 2.3.4
	- TclOO 0.7
	- tdbc 1.0b17
	- Thread 2.7b1
		New command: [thread::cancel]

    * Fixed several clip region issues.

    * Fixed crash in tearoff menus.

    * Made [auto_execok] search match that for [exec].

    * Several fixes to stacked zlib (de)compression channels

    * Mac OS X versions less than 10.4 (Tiger) no longer supported.
Tcl Core Team and Maintainers
Don Porter, Tcl Core Release Manager