Linuxeden开源社区时隔一年，Tcl/Tk 核心团队隆重推出了 Tcl/Tk 8.6 项目的最新版本 8.6.7。该版本修复了诸多 bug，并实现了两个 Tcl 改进提案（Tcl Improvement Proposal），引进了 Windows 上的多媒体键支持。此外，Unicode 支持更新到了 10.0。
更新内容：
* [TIP 473] (TclOO 1.1.0) Let [oo::copy] specify target namespace
* [TIP 464] Support multimedia keys on Windows
* Revise Tcl_LinkVar to tolerate some prefixes
*** POTENTIAL INCOMPATIBILITY ***
* Allow empty command as [interp alias] target
*** POTENTIAL INCOMPATIBILITY ***
* Revise Tcl_UtfToUniChar() handling of invalid UTF-8
*** POTENTIAL INCOMPATIBILITY ***
* [clock] and [encoding] are now ensembles
* Several [clock] subcommands are now compiled to bytecode
* Fix crashes or hangs in…
– [socket -async ::1 0] with no host
– Threaded memory allocator in thread finalization
– Tcl_ListObjReplace() error when passed NULL interp
– [binary scan a$n] when $n overflows int
– [lsort -unique [lrepeat [expr {1<<27}] 1]]
– Drawing many dashed canvas objects
– Using Tk after IME restart
– Warp pointer operations
– [[text .t] insert 0.0 \na; .t replace 2.0 3.0 b]
– Resource exhaustion processing corrupt GIF
* Fix memory leaks in…
– namespace delete when unset trace revives namespace variable.
– Deletion of the [history] command
– http::geturl when keep-alive is denied
– TclJoinPath on a custom Tcl_Filesystem
– text BTree operations
* Update Unicode data to 10.0
*** POTENTIAL INCOMPATIBILITY ***
* Merge updates from new libtommath release; purge unused files
*** POTENTIAL INCOMPATIBILITY ***
* Update bundled zlib to release 1.2.11
* Remove legacy support macro panic() – conflicts with system libs
*** POTENTIAL INCOMPATIBILITY ***
* Revise Tk font support to avoid type mismatch with recent Xft
* Repair cmd resolver caching, demonstrated by tests resolver-3.1*
* Repair zlib stream buffer flushing; zlib-7.8 and PNG writing
* Prevent Win thread termination during init and teardown
* Make KeyRelease event handling get _L and _R right
* Repaint ttk::button when its image changes
* Wrapped text don’t start lines with whitespace
* Non-native themes properly display tri-state buttons
* File dialog repairs for -typevariable, -initialdir, -initialfile
* Avoid unreleasable global grab due to menu keyboard traversal
* Fix Win regression [event generate .e <diaeresis>]
* Fix [grid configure -in] to fully clear outdated info
* Fix ttk::combobox proper style with -postoffset (test combobox-3)
* OSX: Stop [$text bbox] returning negative width
* Repair autoloader fragility loading procs that call tailcall
* Correct parsing in [scan 0x1 %b], [scan 0x1 %o]
* Fix [string replace] so test stringComp-14.5 passes
* Invalidate VFS mounts on sytem encoding change
* Fix [expr {NaN > “Gran”}] to return 1; string comparison
* Stop frequent Tcl_GetTime() calls creating clock drift
* Correct functioning of dynamic unexport of methods
* Fix [file join a //b] and [file join //a b]
* Compute correct warp cursor position on 2nd display
* Enable dismissal of ttk::menubutton without hover
* Tk_BindEvent filter events Tk ignores avoid X11 ring buffer flood
* Allow [$photo read] to read files beginning with “-“
* [text] redisplay calculations corrected on OSX
* Fix drawing of long text lines on Windows
* Disabled combobox arrow appearance (danckaert)
* Fix {PNG -alpha} format for 16-bit color
* Workaround X11 drawing defects in Ubuntu 16.10+
* Fix calculation of ttk::notebook tab widths and tab user management
* Scidb race in notebook tab selection
* Color name parsing set to reject invalid hex color codes (#ABCZ)
* OSX scrollbar draw position, highlights, & smooth scroll
* Race condition on Win clipboard cleanup
* Center image on button
* Paneconfigure get pane heights right
* Windows: User switch forced theme reset
* Updated bundled packages
– Itcl 4.1.0 (incompatible with Itk 4.0, get Itk 4.1)
– sqlite3 3.20.0
– Thread 2.8.1
– tdbc* 1.0.5
– http 2.8.11
– tcltest 2.4.1
– msgcat 1.6.1
转自 https://www.oschina.net/news/87619/tcltk-8-6-7