Before You Begin

dbx is an interactive, source-level, command-line debugging tool. Debugging a Program With dbx is intended for programmers with a working knowledge of Fortran, C, or C++, and some understanding of the Solaris operating environment and UNIX^® commands, who want to debug an application using dbx commands.

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How This Book Is Organized

Debugging a Program With dbx contains the following chapters and appendixes:

Chapter 1 gives you the basics of using dbx to debug an application.

Chapter 2 describes how to start a debugging session, discusses compilation options, and tells you how to save all or part of session and replay it later.

Chapter 3 describes how to set dbx environment variables to customize your debugging environment and how to use the initialization file, .dbxrc, to preserve changes and adjustments from session to session.

Chapter 4 tells you about visiting source files and functions; locating symbols; and looking up variables, members, types, and classes.

Chapter 5 describes how to run, attach to, detach from,. continue execution of, stop, and rerun a program under dbx. It also tells you how to single-step through program code.

Chapter 6 describes how to set, clear, and list breakpoints and traces.

Chapter 7 tells you how to examine the call stack and how to debug a core file.

Chapter 8 shows you how to evaluate data; display the values of expressions, variables, and other data structures; and assign values to variables.

Chapter 9 describes how to use runtime checking to detect memory leak and memory access errors in your program automatically.

Chapter 10 describes the fix and continue feature of dbx that allows you to modify and recompile a source file and continue executing without rebuilding your entire program.

Chapter 11 tells you how to find information about threads.

Chapter 12 describes several dbx facilities that help you debug child processes.

Chapter 13 tells you how to use dbx to work with signals.

Chapter 14 describes dbx support of C++ templates, and the commands available for handling C++ exceptions and how dbx handles these exceptions.

Chapter 15 introduces some of the dbx facilities you can use to debug a Fortran program.

Chapter 16 describes how you can use dbx to debug an application that is a mixture of Java code and C JNI (Java Native Interface) code or C++ JNI code.

Chapter 17 tells you how to use event management and execution control command at the machine-instruction level, how to display the contents of memory at specific addresses, and how to display source code lines along with their corresponding machine instructions.

Chapter 18 explains the differences between ksh-88 and dbx commands.

Chapter 19 describes dbx support for program that use dynamically linked, shared libraries.

Appendix A focuses on dbx commands that change your program or its behavior when you run it under dbx.

Appendix B tells you how to manage events, and describes how dbx can perform specific actions when specific events occur in the program you are debugging.

Appendix C gives detailed syntax and functional descriptions of all of the dbx commands.

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Typographic Conventions

TABLE P-1 Typeface Conventions

Typeface	Meaning	Examples
AaBbCc123	The names of commands, files, and directories; on-screen computer output	Edit your .login file. Use ls -a to list all files. % You have mail.
AaBbCc123	What you type, when contrasted with on-screen computer output	% su Password:
AaBbCc123	Book titles, new words or terms, words to be emphasized	Read Chapter 6 in the User's Guide. These are called class options. You must be superuser to do this.
AaBbCc123	Command-line placeholder text; replace with a real name or value	To delete a file, type rm filename.

TABLE P-2 Code Conventions

Code Symbol	Meaning	Notation	Code Example
[ ]	Brackets contain arguments that are optional.	O[n]	O4, O
{ }	Braces contain a set of choices for required option.	d{y|n}	dy
|	The "pipe" or "bar" symbol separates arguments, only one of which may be chosen.	B{dynamic|static}	Bstatic
:	The colon, like the comma, is sometimes used to separate arguments.	Rdir[:dir]	R/local/libs:/U/a
...	The ellipsis indicates omission in a series.	xinline=f1[,...fn]	xinline=alpha,dos

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Shell Prompts

Shell	Prompt
C shell	%
Bourne shell and Korn shell	$
C shell, Bourne shell, and Korn shell superuser	#

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Accessing Forte Developer Development Tools and Man Pages

The Forte Developer product components and man pages are not installed into the standard /usr/bin/ and /usr/share/man directories. To access the Forte Developer compilers and tools, you must have the Forte Developer component directory in your PATH environment variable. To access the Forte Developer man pages, you must have the Forte Developer man page directory in your MANPATH environment variable.

For more information about the PATH variable, see the csh(1), sh(1), and ksh(1) man pages. For more information about the MANPATH variable, see the man(1) man page. For more information about setting your PATH and MANPATH variables to access this Forte Developer release, see the installation guide or your system administrator.

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Note - The information in this section assumes that your Forte Developer products are installed in the /opt directory. If your product software is not installed in the /opt directory, ask your system administrator for the equivalent path on your system.

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Accessing Forte Developer Compilers and Tools

Use the steps below to determine whether you need to change your PATH variable to access the Forte Developer compilers and tools.

To Determine Whether You Need to Set Your PATH Environment Variable

1. Display the current value of the PATH variable by typing the following at a command prompt: