console(3tk)

📦
version 9.0.4 · 3 versions
, in ubuntu questing, ubuntu resolute, ubuntu stonking

✨ console — the manual page 💖

ok so bestie, this is console(3tk), a Tk built-in command, and it's literally the whole vibe of "what if there was no terminal but we made one anyway" 🌈

🌸 NAME 🌸

console — control the console on systems that don't have a real console 💅

🎀 SYNOPSIS 🎀

console subcommand ?arg ...?

🦋 DESCRIPTION 🦋

ok so picture this: some platforms just. don't have a real console. tragic. so the console window shows up as a glow-up replacement, letting input and output happen on the standard I/O channels anyway 🫶

It's implemented as a separate interpreter with the Tk toolkit loaded, and you get control over that interpreter through the console command. The behaviour of the console window is defined mainly through the contents of the console.tcl file in the Tk library. no cap.

Except for TkAqua, this command is not available when Tk is loaded into a tclsh interpreter with package require tk, because in that case a conventional terminal is expected to be present. (ik, rude.)

In TkAqua, this command is disabled when there is a startup script and stdin is /dev/null — which is the case e.g. when a bundled application embedding Tk is started by the macOS Launcher 😭

To enable the command in that case, define the environment variable TK_CONSOLE. You can do that by modifying the Info.plist file: add the LSEnvironment key to the main dict, and set its value to be a dict with the key TK_CONSOLE. slay, plist editing, the main character energy of config files ✨

🌟 console subcommands 🌟

  • console eval script — evaluates the script argument as a Tcl script in the console interpreter. The normal interpreter is accessed through the consoleinterp command in the console interpreter. iykyk 🔥
  • console hide — hides the console window from view. Precisely equivalent to withdrawing the . window in the console interpreter. poof, gone, ghosted 🙈
  • console show — displays the console window. Precisely equivalent to deiconifying the . window in the console interpreter. she's back 💖
  • console title ?string? — query or modify the title of the console window. If string is not specified, it queries the title of the console window; otherwise it sets the title of the console window to string. Precisely equivalent to using the wm title command in the console interpreter. name her, bestie 🎀

💜 ACCESS TO THE MAIN INTERPRETER 💜

The consoleinterp command in the console interpreter lets scripts be evaluated in the main interpreter. It supports two subcommands: eval and record 👑

  • consoleinterp eval script — evaluates script as a Tcl script at the global level in the main interpreter.
  • consoleinterp record script — records and evaluates script as a Tcl script at the global level in the main interpreter, as if script had been typed in at the console. it's giving "pretend you typed it yourself" 💅

🧚 ADDITIONAL TRAP CALLS 🧚

There are several additional commands in the console interpreter that get called in response to activity in the main interpreter. These are documented here for completeness only — they form part of the internal implementation of the console and are likely to change or be modified without warning 💀 so don't get attached, bestie.

Output to the console from the main interpreter via the stdout and stderr channels is handled by invoking the tk::ConsoleOutput command in the console interpreter with two arguments. The first argument is the name of the channel being written to, and the second argument is the string being written to the channel — and yes, that's after encoding and end-of-line translation processing has been performed. 🔍

When the . window of the main interpreter is destroyed, the tk::ConsoleExit command in the console interpreter is called — assuming the console interpreter hasn't already been deleted itself, that is. 😭

⭐ DEFAULT BINDINGS ⭐

The default script creates a console window (implemented using a text widget) that has the following behaviour:

  1. Pressing the tab key inserts a TAB character (as defined by the Tcl \t escape.)
  2. Pressing the return key causes the current line (if complete by the rules of info complete) to be passed to the main interpreter for evaluation.
  3. Pressing the delete key deletes the selected text (if any text is selected) or the character to the right of the cursor (if not at the end of the line.)
  4. Pressing the backspace key deletes the selected text (if any text is selected) or the character to the left of the cursor (of not at the start of the line.)
  5. Pressing either Control+A or the home key causes the cursor to go to the start of the line (but after the prompt, if a prompt is present on the line.)
  6. Pressing either Control+E or the end key causes the cursor to go to the end of the line.
  7. Pressing either Control+P or the up key causes the previous entry in the command history to be selected.
  8. Pressing either Control+N or the down key causes the next entry in the command history to be selected.
  9. Pressing either Control+B or the left key causes the cursor to move one character backward as long as the cursor is not at the prompt.
  10. Pressing either Control+F or the right key causes the cursor to move one character forward.
  11. Pressing F9 rebuilds the console window by destroying all its children and reloading the Tcl script that defined the console's behaviour. it's giving factory reset 🔥

Most other behaviour is the same as a conventional text widget — except for the way that the <<Cut>> event is handled identically to the <<Copy>> event. (yes, cut is just copy here. we don't talk about it. 💀)

🌈 EXAMPLE 🌈

Not all platforms have the console command, so debugging code often has the following code fragment in it so output produced by puts can be seen while during development:

catch {console show}

🔥 SEE ALSO 🔥

👑 KEYWORDS 👑

console, interpreter, window, interactive, output channels

and that's the whole page, bestie!! this one's from Tk version 8.4 and it's console(3tk) — go forth and console show responsibly 💖✨🎀

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