21. Command Interpreters

No value for GDBN supports multiple command interpreters, and some command infrastructure to allow users or user interface writers to switch between interpreters or run commands in other interpreters.

No value for GDBN currently supports two command interpreters, the console interpreter (sometimes called the command-line interpreter or CLI) and the machine interface interpreter (or GDB/MI). This manual describes both of these interfaces in great detail.

By default, No value for GDBN will start with the console interpreter. However, the user may choose to start No value for GDBN with another interpreter by specifying the ‘-i’ or ‘--interpreter’ startup options. Defined interpreters include:

console

The traditional console or command-line interpreter. This is the most often used interpreter with No value for GDBN. With no interpreter specified at runtime, No value for GDBN will use this interpreter.

mi

The newest GDB/MI interface (currently mi2). Used primarily by programs wishing to use No value for GDBN as a backend for a debugger GUI or an IDE. For more information, see The GDB/MI Interface.

mi2

The current GDB/MI interface.

mi1

The GDB/MI interface included in No value for GDBN 5.1, 5.2, and 5.3.

The interpreter being used by No value for GDBN may not be dynamically switched at runtime. Although possible, this could lead to a very precarious situation. Consider an IDE using GDB/MI. If a user enters the command "interpreter-set console" in a console view, No value for GDBN would switch to using the console interpreter, rendering the IDE inoperable!

Although you may only choose a single interpreter at startup, you may execute commands in any interpreter from the current interpreter using the appropriate command. If you are running the console interpreter, simply use the interpreter-exec command:

interpreter-exec mi "-data-list-register-names"

GDB/MI has a similar command, although it is only available in versions of No value for GDBN which support GDB/MI version 2 (or greater).