System Debug Reference Manual (32650-90888)

18 Chapter1
INTRODUCTION
What Is Debug?
What Is Debug?
Debug provides non-privileged and privileged users with both interactive and
programmatic debugging facilities for examining their operating environments.
Debug enables you to do the following:
• Set, delete, and list breakpoints in a program. The program executes until a breakpoint
is reached, then stops and passes control to the user. When you set breakpoints, you can
specify a list of commands that automatically are executed when the breakpoint is hit.
• Single step (multiple steps) through a program.
• Display and/or modify the contents of memory locations. A full set of addressing modes
is offered, including absolute CM memory, code segment relative, data segment relative,
S relative, Q relative, DB relative, HP Precision Architecture virtual addresses, and HP
Precision Architecture real memory addresses.
• Display a symbolic procedure stack trace, optionally displaying interleaved NM and CM
calls. You can also set the current debug environment back temporarily to the
environment which existed at any marker on the stack.
• Calculate the value of expressions in order to determine the correct values of variables
at a given point in a program. Values can be custom formatted in several bases.
• Use new full screen displays (windows) which allow inspection of registers, program
code, the current stack frame, and the top of stack. Groups of custom user windows can
be aimed at important data blocks to monitor changing values dynamically.
• Display online help for all commands, predefined functions, and environment variables.
• Create and reference user-defined variables.
• Define powerful parameterized macros. Macros can be invoked as new commands to
perform useful sequences of commands, or as functions within expressions that return
single values.
• Define aliases for command and macro names.
• Execute commands from a file, record all user input to a log file, and record all Debug
output to a list file.
What Is the Dump Analysis Tool (DAT)?
The Dump Analysis Tool (DAT) aids support and lab personnel in analyzing MPE XL
system events such as process hangs, operating system failures, or hardware failures. This
tool is used primarily by Hewlett-Packard support personnel.
Refer to chapter 9 for detailed information regarding DAT.
What Is the Standalone Analysis Tool (SAT)?
The Standalone Analysis Tool (SAT) aids support and lab personnel in analyzing MPE XL
system events such as process hangs, operating system failures, and hardware failures.