1. Forum
  2. Newsgroups
  3. comp.lang.tcl

  • Tcl 9.1a1 RELEASED

    From Don Porter@[email protected] to comp.lang.tcl on Thu Mar 5 15:46:22 2026
    From Newsgroup: comp.lang.tcl


    Tcl 9.1a1 Release Announcement
    ==============================

    March 4, 2026

    The Tcl Core Team is pleased to announce the release of Tcl 9.1a1.
    This is the second alpha release of Tcl 9.1.

    Tcl is the Tool Command Language originated by John Ousterhout and his
    team at U.C. Berkeley in the late 1980s. Its development is continued
    by the efforts of a global network of volunteers guided by the Tcl Core Team.

    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. Such reports can be submitted here.

    [Tcl Ticket Tracker](https://core.tcl-lang.org/tcl/ticket)

    We ask that you log in (anonymous if you wish) to create tickets.
    This deters abuse of the ticketing system:

    [Tcl Contributor Login](https://core.tcl-lang.org/tcl/login)

    Where to get the new releases
    =============================

    Tcl 9.1a1 sources are freely available as open source from the Tcl
    SourceForge project's file distribution area:

    [Tcl Source Distribution](https://sourceforge.net/projects/tcl/files/)

    The Tcl 9.1a1 distribution is source code only. We keep links to some
    third parties offering pre-built binaries for various systems here:

    [Tcl Binary Distribution](https://www.tcl-lang.org/software/tcltk/bindist.html)

    Tcl Summary
    ===========

    The Tcl distribution delivers C source code that builds into a C library providing interpreters and related supports to execute programs written
    in the Tcl programming language. Source code for the application program `tclsh` is also included. `tclsh` provides a shell for either interactive execution of Tcl commands, or execution of files containing Tcl programs.

    Tcl is an extensible language, and the Tcl C library provides interfaces
    for the creation of extension libraries adding new commands and features
    to the core Tcl command set. Tcl 9 debuts the full feature set needed to package an application written in C and Tcl into a single file executable exploiting virtual filesystem archives.

    Tcl 9.1 Release Summary
    =======================

    This is a new minor version of Tcl 9. When compared with the prior release
    Tcl 9.0, there are new features and interfaces. Tcl 9.1 should remain compatible with scripts and packages written to the public interfaces of
    Tcl 9.0. A summary of the most noteworthy changes is found below.

    Tcl Improvement Proposals (TIPs)
    ================================

    Each new user-visible feature in Tcl should find its origins in a Tcl Improvement Proposal (TIP). TIPs are published, edited, considered and
    voted in public, and should contain valuable information about how a
    feature came to be the way it is. See the full collection here:

    [TIP Index](https://tip.tcl-lang.org/)

    Tcl Changes Summary
    ===================

    (from changes.md in the source code distribution)

    The source code for Tcl is managed by fossil. Tcl developers coordinate all changes to the Tcl source code at

    [Tcl Source Code](https://core.tcl-lang.org/tcl/timeline)

    Release Tcl 9.1a1 arises from the check-in with tag `core-9-1-a1`.

    Highlighted differences between Tcl 9.1 and Tcl 9.0 are summarized below,
    with focus on changes important to programmers using the Tcl library and writing Tcl scripts.

    # New commands and options

    - [New options -backslashes, -commands and -variables for subst command](https://core.tcl-lang.org/tips/doc/trunk/tip/712.md)
    - [New command unicode for Unicode normalization](https://core.tcl-lang.org/tips/doc/trunk/tip/726.md)
    - [New timer command, switch to monotonic clock and microsecond resolution](https://core.tcl-lang.org/tips/doc/trunk/tip/723.md)

    # New public C API

    - [Tcl\_IsEmpty checks if the string representation of a value would be the empty string](https://core.tcl-lang.org/tips/doc/trunk/tip/711.md)
    - [Tcl\_GetEncodingNameForUser returns name of encoding from user settings](https://core.tcl-lang.org/tips/doc/trunk/tip/716.md)
    - [Tcl\_AttemptCreateHashEntry - version of Tcl\_CreateHashEntry that returns NULL instead of panic'ing on memory allocation errors](https://core.tcl-lang.org/tips/doc/trunk/tip/717.md)
    - [Tcl\_ListObjRange, Tcl\_ListObjRepeat, Tcl\_TclListObjReverse - C API for new list operations](https://core.tcl-lang.org/tips/doc/trunk/tip/649.md)
    - [Tcl\_UtfToNormalized, Tcl\_UtfToNormalizedDString - C API for Unicode normalization](https://core.tcl-lang.org/tips/doc/trunk/tip/726.md)
    - [Tcl\_UtfToExternalEx and Tcl\_ExternalToUtfEx - C encoding API supporting output buffers larger than INT_MAX](https://core.tcl-lang.org/tips/doc/trunk/tip/737.md)
    - [New API for monotonic clock and microseconds resolution](https://core.tcl-lang.org/tips/doc/trunk/tip/723.md)

    # Changes in interpreter initialization

    - [Custom applications must call Tcl\_FindExecutable or TclZipfs_AppHook to initialize Tcl](https://core.tcl-lang.org/tips/doc/trunk/tip/732.md) *Potential incompatibility*
    - [Search path for locating Tcl core script and encodings is changed](https://core.tcl-lang.org/tips/doc/trunk/tip/732.md) *Potential incompatibility*

    # Performance

    - [Memory efficient internal representations](https://core.tcl-lang.org/tcl/wiki?name=New+abstract+list+representations)
    for list operations on large lists.
    - [Continued 64-bit capacity: Command line arguments larger than 2Gb](https://core.tcl-lang.org/tips/doc/trunk/tip/626.md)
    - Speedup in interpreter creation

    # Bug fixes
    - [tclEpollNotfy PlatformEventsControl panics if websocket disconnected](https://core.tcl-lang.org/tcl/tktview/010d8f38)

    For additional information:
    ===========================

    Please visit the Tcl Developer Xchange web site:

    [Tcl Developer Xchange](https://www.tcl-lang.org/)

    This site contains a variety of information about Tcl/Tk in general, the
    core Tcl and Tk distributions, Tcl development tools, and much more.
    --
    Tcl Core Team and Maintainers
    Don Porter, Tcl Core Release Manager
    --
    | Don Porter Applied and Computational Mathematics Division |
    | [email protected] Information Technology Laboratory |
    | http://math.nist.gov/~DPorter/ NIST | |______________________________________________________________________|

    --- Synchronet 3.21d-Linux NewsLink 1.2
  • From Harald Oehlmann@[email protected] to comp.lang.tcl on Thu Mar 5 23:13:22 2026
    From Newsgroup: comp.lang.tcl

    GREAT !
    My appreciation to the whole team to make this happen !!!

    Harald

    Am 05.03.2026 um 21:46 schrieb Don Porter:

    Tcl 9.1a1 Release Announcement
    ==============================

    March 4, 2026

    The Tcl Core Team is pleased to announce the release of Tcl 9.1a1.
    This is the second alpha release of Tcl 9.1.

    Tcl is the Tool Command Language originated by John Ousterhout and his
    team at U.C. Berkeley in the late 1980s.  Its development is continued
    by the efforts of a global network of volunteers guided by the Tcl Core Team.

    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. Such reports can be submitted here.

    [Tcl Ticket Tracker](https://core.tcl-lang.org/tcl/ticket)

    We ask that you log in (anonymous if you wish) to create tickets.
    This deters abuse of the ticketing system:

    [Tcl Contributor Login](https://core.tcl-lang.org/tcl/login)

    Where to get the new releases
    =============================

    Tcl 9.1a1 sources are freely available as open source from the Tcl SourceForge project's file distribution area:

    [Tcl Source Distribution](https://sourceforge.net/projects/tcl/files/)

    The Tcl 9.1a1 distribution is source code only.  We keep links to some
    third parties offering pre-built binaries for various systems here:

    [Tcl Binary Distribution](https://www.tcl-lang.org/software/tcltk/
    bindist.html)

    Tcl Summary
    ===========

    The Tcl distribution delivers C source code that builds into a C library providing interpreters and related supports to execute programs written
    in the Tcl programming language.  Source code for the application program `tclsh` is also included.  `tclsh` provides a shell for either interactive execution of Tcl commands, or execution of files containing Tcl programs.

    Tcl is an extensible language, and the Tcl C library provides interfaces
    for the creation of extension libraries adding new commands and features
    to the core Tcl command set.  Tcl 9 debuts the full feature set needed to package an application written in C and Tcl into a single file executable exploiting virtual filesystem archives.

    Tcl 9.1 Release Summary
    =======================

    This is a new minor version of Tcl 9.  When compared with the prior release Tcl 9.0, there are new features and interfaces.  Tcl 9.1 should remain compatible with scripts and packages written to the public interfaces of
    Tcl 9.0.  A summary of the most noteworthy changes is found below.

    Tcl Improvement Proposals (TIPs)
    ================================

    Each new user-visible feature in Tcl should find its origins in a Tcl Improvement Proposal (TIP).  TIPs are published, edited, considered and voted in public, and should contain valuable information about how a
    feature came to be the way it is.  See the full collection here:

    [TIP Index](https://tip.tcl-lang.org/)

    Tcl Changes Summary
    ===================

    (from changes.md in the source code distribution)

    The source code for Tcl is managed by fossil.  Tcl developers coordinate all
    changes to the Tcl source code at

    [Tcl Source Code](https://core.tcl-lang.org/tcl/timeline)

    Release Tcl 9.1a1 arises from the check-in with tag `core-9-1-a1`.

    Highlighted differences between Tcl 9.1 and Tcl 9.0 are summarized below, with focus on changes important to programmers using the Tcl library and writing Tcl scripts.

    # New commands and options

    - [New options -backslashes, -commands and -variables for subst command] (https://core.tcl-lang.org/tips/doc/trunk/tip/712.md)
    - [New command unicode for Unicode normalization](https://core.tcl- lang.org/tips/doc/trunk/tip/726.md)
    - [New timer command, switch to monotonic clock and microsecond resolution](https://core.tcl-lang.org/tips/doc/trunk/tip/723.md)

    # New public C API

    - [Tcl\_IsEmpty checks if the string representation of a value would be
    the empty string](https://core.tcl-lang.org/tips/doc/trunk/tip/711.md)
    - [Tcl\_GetEncodingNameForUser returns name of encoding from user settings](https://core.tcl-lang.org/tips/doc/trunk/tip/716.md)
    - [Tcl\_AttemptCreateHashEntry - version of Tcl\_CreateHashEntry that returns NULL instead of panic'ing on memory allocation errors](https:// core.tcl-lang.org/tips/doc/trunk/tip/717.md)
    - [Tcl\_ListObjRange, Tcl\_ListObjRepeat, Tcl\_TclListObjReverse - C API
    for new list operations](https://core.tcl-lang.org/tips/doc/trunk/ tip/649.md)
    - [Tcl\_UtfToNormalized, Tcl\_UtfToNormalizedDString - C API for Unicode normalization](https://core.tcl-lang.org/tips/doc/trunk/tip/726.md)
    - [Tcl\_UtfToExternalEx and Tcl\_ExternalToUtfEx - C encoding API
    supporting output buffers larger than INT_MAX](https://core.tcl- lang.org/tips/doc/trunk/tip/737.md)
    - [New API for monotonic clock and microseconds resolution](https:// core.tcl-lang.org/tips/doc/trunk/tip/723.md)

    # Changes in interpreter initialization

    - [Custom applications must call Tcl\_FindExecutable or TclZipfs_AppHook
    to initialize Tcl](https://core.tcl-lang.org/tips/doc/trunk/tip/732.md) *Potential incompatibility*
    - [Search path for locating Tcl core script and encodings is changed] (https://core.tcl-lang.org/tips/doc/trunk/tip/732.md) *Potential incompatibility*

    # Performance

    - [Memory efficient internal representations](https://core.tcl-lang.org/ tcl/wiki?name=New+abstract+list+representations)
    for list operations on large lists.
    - [Continued 64-bit capacity: Command line arguments larger than 2Gb] (https://core.tcl-lang.org/tips/doc/trunk/tip/626.md)
    - Speedup in interpreter creation

    # Bug fixes
     - [tclEpollNotfy PlatformEventsControl panics if websocket disconnected](https://core.tcl-lang.org/tcl/tktview/010d8f38)

    For additional information:
    ===========================

    Please visit the Tcl Developer Xchange web site:

    [Tcl Developer Xchange](https://www.tcl-lang.org/)

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


    --- Synchronet 3.21d-Linux NewsLink 1.2