Tornado

Tornado 2.0
User’s Guide
– A button, akin to the button, to launch a dedicated window that
monitors the value where this points.
The Tcl primitive catch is used in the second button definition in order to avoid
propagating error conditions (for instance, if the buttons are pressed with no code
loaded) from GDB back to the controlling CrossWind session. This does not
prevent GDB from issuing the appropriate error messages to the command panel.
Example 7-1
Buttons for C++ this Pointer
# Make a nice gap before new buttons
toolBarItemCreate " " space
# BUTTON: "t" Print C++ "this" value.
toolBarItemCreate " t " button {
ttySend "print this\n"
}
# BUTTON: "t*" Launch "inspect" window on current C++ class (*this)
toolBarItemCreate " t*" button {
catch {downtcl gdb display/W *this}
}
Tcl: A List Command for the File Menu
Example 7-2 illustrates how to add extensions to the CrossWind graphical
interface with a simple enhancement: adding a menu command to list the
displayed program source centered on a particular line.
In Example 7-2, the procedure xwindList uses downtcl to run the GDB list
command. To tie this into the graphical interface, the example adds a new
command List from… to the File menu. The new command displays a form
(described in the dialogCreate call) to collect input specifying an argument to the
list command. When input is complete, the form in turn runs xwindList, through
a call-back attached to its OK button. Figure 7-14 shows the new menu command
and form defined here (and the Example 7-3 menu command).
Example 7-2
List Command
# FORM: a form to prompt for list argument
# (part of "List from..." command addition to "File" menu)
dialogCreate "List from?" -size 290 100 {
{text "line spec:" -hspan}
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