Using the graphical interface of debug

Source pane

The Source pane displays the current source file. Whenever the current process or thread stops, the file is positioned to display the current line in the current function. The current line is highlighted, and also indicated by an arrow in the left margin. If there is no current file, or the file was not compiled with debugging information, the Source pane will be empty. The Source pane will also be empty if the debugger cannot find the current file; in that case you can use the ``Source Path'' popup to change the path the debugger uses to search for source files.

The Source pane allows editing as well as viewing of the current source file. See ``Source editing''.

A stop sign appears in the left margin for each line that has a breakpoint set on it. You may set or remove a breakpoint by clicking the SELECT button in the left margin of the selected line. The debugger will display a message if it is unable
to set the breakpoint on the selected line. There are several reasons why it may not be able to set the breakpoint:

The source line does not contain anything that would generate executable code. This would include blank lines and lines containing only comments and variable declarations.
The line is part of a multi-line statement. You may set a breakpoint on only one line of a multi-line statement or condition.
The line is the beginning of a function definition. Set the breakpoint on the first statement in the function instead.

You may also view other files in the Source pane, either by opening another file from the list in the ``Open Source'' popup window, or by viewing a different function from the list in the ``Show Function Source'' popup window.

You may examine other source files while still viewing the file in the Source pane by creating a secondary source window. Secondary source windows are created by selecting the ``New Source'' option. In the default configuration, each secondary source window consists of a ``Status pane'' and a Source pane. The Source pane of a secondary source window is not updated when the current process or thread stops.