ULTRIX Worksystem Software Guide to the dxdb Debugger

This document, the "Guide to the dxdb Debugger" for ULTRIX Worksystem Software (Version 2.2, for ULTRIX-32 3.1 or higher), is a technical manual published by Digital Equipment Corporation (1988/1989). It is aimed at programmers familiar with general debugging techniques and the DECwindows interface.

The guide provides comprehensive instructions on how to use the dxdb debugger, a DECwindows utility, to debug C programs. It details the debugger's graphical user interface, including its various windows (Control, Source, Examine, Stack, Dump, Make, Run, Input/Output) and their associated menus and commands.

Key functionalities covered include:

• Starting and Exiting the dxdb debugger.
• Viewing and Browsing Source Files within the debugger.
• Running a Program, including supplying command-line arguments.
• Setting and Managing Breakpoints (global, line, function, and conditional) to pause program execution.
• Setting and Managing Tracepoints (global, line, function, and conditional) to print variable values without pausing.
• Controlling Program Execution using step, skip, continue, stop, and return functions.
• Inspecting and Modifying Variables (printing, examining specific variables in a dedicated window, assigning new values, and viewing all active local variables in a dump window).
• Obtaining Information About Variables (data type, scope, and location) using Whatis, Which, and Whereis functions.
• Viewing the Program Execution Stack to trace routine calls and parameters.
• Editing Files directly from the debugger.
• Restarting the Debugger Session and rebuilding the executable program.

The guide illustrates these operations through a practical debugging session of a sample C dice-rolling program (diroll and didisp.c), demonstrating how to identify and correct common programming errors.