1console(n) Tk Built-In Commands console(n)
2______________________________________________________________________________
6
8 console - Control the console on systems without a real console
9
11 console subcommand ?arg ...?
12_________________________________________________________________
13
15 The console window is a replacement for a real console to allow input
16 and output on the standard I/O channels on platforms that do not have a
17 real console. It is implemented as a separate interpreter with the Tk
18 toolkit loaded, and control over this interpreter is given through the
19 console command. The behaviour of the console window is defined mainly
20 through the contents of the console.tcl file in the Tk library. Except
21 for TkAqua, this command is not available when Tk is loaded into a
22 tclsh interpreter with “package require Tk”, as a conventional terminal
23 is expected to be present in that case. In TkAqua, this command is ony
24 available when stdin is /dev/null (as is the case e.g. when the appli‐
25 cation embedding Tk is started from the Mac OS X Finder).
26 console eval script
28 Evaluate the script argument as a Tcl script in the console
29 interpreter. The normal interpreter is accessed through the
30 consoleinterp command in the console interpreter.
31 console hide
33 Hide the console window from view. Precisely equivalent to
34 withdrawing the . window in the console interpreter.
35 console show
37 Display the console window. Precisely equivalent to deiconify‐
38 ing the . window in the console interpreter.
39 console title ?string?
41 Query or modify the title of the console window. If string is
42 not specified, queries the title of the console window, and sets
43 the title of the console window to string otherwise. Precisely
44 equivalent to using the wm title command in the console inter‐
45 preter.
46
48 The consoleinterp command in the console interpreter allows scripts to
49 be evaluated in the main interpreter. It supports two subcommands:
50 eval and record.
51 consoleinterp eval script
53 Evaluates script as a Tcl script at the global level in the main
54 interpreter.
55 consoleinterp record script
57 Records and evaluates script as a Tcl script at the global level
58 in the main interpreter as if script had been typed in at the
59 console.
60
62 There are several additional commands in the console interpreter that
63 are called in response to activity in the main interpreter. These are
64 documented here for completeness only; they form part of the internal
65 implementation of the console and are likely to change or be modified
66 without warning.
67 Output to the console from the main interpreter via the stdout and
69 stderr channels is handled by invoking the tk::ConsoleOutput command in
70 the console interpreter with two arguments. The first argument is the
71 name of the channel being written to, and the second argument is the
72 string being written to the channel (after encoding and end-of-line
73 translation processing has been performed.)
74 When the . window of the main interpreter is destroyed, the tk::Con‐
76 soleExit command in the console interpreter is called (assuming the
77 console interpreter has not already been deleted itself, that is.)
78
80 The default script creates a console window (implemented using a text
81 widget) that has the following behaviour:
82 [1] Pressing the tab key inserts a TAB character (as defined by the
84 Tcl \t escape.)
85 [2] Pressing the return key causes the current line (if complete by
87 the rules of info complete) to be passed to the main interpreter
88 for evaluation.
89 [3] Pressing the delete key deletes the selected text (if any text
91 is selected) or the character to the right of the cursor (if not
92 at the end of the line.)
93 [4] Pressing the backspace key deletes the selected text (if any
95 text is selected) or the character to the left of the cursor (of
96 not at the start of the line.)
97 [5] Pressing either Control+A or the home key causes the cursor to
99 go to the start of the line (but after the prompt, if a prompt
100 is present on the line.)
101 [6] Pressing either Control+E or the end key causes the cursor to go
103 to the end of the line.
104 [7] Pressing either Control+P or the up key causes the previous
106 entry in the command history to be selected.
107 [8] Pressing either Control+N or the down key causes the next entry
109 in the command history to be selected.
110 [9] Pressing either Control+B or the left key causes the cursor to
112 move one character backward as long as the cursor is not at the
113 prompt.
114 [10] Pressing either Control+F or the right key causes the cursor to
116 move one character forward.
117 [11] Pressing F9 rebuilds the console window by destroying all its
119 children and reloading the Tcl script that defined the console's
120 behaviour.
121 Most other behaviour is the same as a conventional text widget except
123 for the way that the <<Cut>> event is handled identically to the
124 <<Copy>> event.
125
127 Not all platforms have the console command, so debugging code often has
128 the following code fragment in it so output produced by puts can be
129 seen while during development:
130 catch {console show}
131
133 destroy(n), fconfigure(n), history(n), interp(n), puts(n), text(n),
134 wm(n)
135
137 console, interpreter, window, interactive, output channels
138Tk 8.4 console(n)