Skip to content
Switch branches/tags
Go to file

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time


Manually copy to a subdirectory of the kernels directory in a Jupyter data location (one of jupyter --paths). See the or kernel.json.linux files for example paths.

Copy one of the kernel.json.... files to kernel.json. Then change the paths in kernel.json to match your machine.

Jupyter will use the kernel.json file to start the kernel (passing the connection file as the first parameter).


If you want to try it out without installation you can use the Binder version in the cloud.

  • Binder (with binary zmq library)
  • Binder (with Tcl zmq)


The Tcl used to run the init.tcl script should have the following available:

Build tclzmq on windows

Easiest way to build tclzmq on Windows is to use mingw.

  • Install tcllib
  • Install critcl
  • Install the msys zmq packages
pacman -Syu mingw64/mingw-w64-x86_64-gcc mingw64/mingw-w64-x86_64-zeromq
  • Run the build.tcl installer from the tclzmq distro. NB: Static builds don't work in the sense that they are the same as shared builds.


Most web client commands are supported. Only thing missing is reading from stdin with for example gets.


  • jupyter::display mimetype body: Display body in the cell. Returns the display id for use in updatedisplay.
  • jupyter::html body: Display body as html in the cell. Returns the display id for use in updatedisplay.
  • jupyter::updatedisplay id mimetype body: Updates the display with id id with then new body.
  • jupyter::updatehtml id body: Updates the html display with id id with the new body.

Magic commands

Magics are lines starting with %% at the top of the cell.

  • %%timeit ?count?: Time the execution of the cell and display the results. Changing count will execute the cell multiple times and show the average time.
  • %%noresult: Do not show the last result. This is convenient if the last result is very large.

Test suite

A prequisite is the jupyter_kernel_test (JKT) module:

pip install jupyter_kernel_test

To run the test suite, execute (from within the checkout directory):

python -m tests.test_tcljupyter



For communication from kernel to session thread [thread::send -async] is being used. stdout and stderr are being intercepted by chan push


Tcl kernel for Jupyter



No releases published


No packages published