7.10 Debugger commands

When the debugger (as opposed to the program being debugged) is interacting with the user, the debugger prints a prompt and reads in a line of text, which it will interpret as its next command line. A command line consists of a single command, or several commands separated by semicolons. Each command consists of several words separated by white space. The first word is the name of the command, while any other words give options and/or parameters to the command.

A word may itself contain semicolons or whitespace if it is enclosed in single quotes (‘'’). This is useful for commands that have other commands as parameters, for example ‘view -w 'xterm -e'’. Characters that have special meaning to ‘mdb’ will be treated like ordinary characters if they are escaped with a backslash (‘\’). It is possible to escape single quotes, whitespace, semicolons, newlines and the escape character itself.

Some commands take a number as their first parameter. For such commands, users can type ‘number command’ as well as ‘command number’. The debugger will treat the former as the latter, even if the number and the command are not separated by white space.