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Source Debugger

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The Helios Source Debugger is a parallel source debugger for the Helios Operating System. It can debug distributed programs running on multiple processors. Modules that require debugging are re-compiled and linked with debug libraries. Debug programs automatically locate a debugger server that displays a source code window for each debug task. Programs can then be debugged in terms of high level source code objects and extensive range of commands.

Tasks can be single stepped, breakpoints set, traced, and variables examined and altered. Fork processes subdivide the window into individual debug child windows. Most of the debugger commands are invoked by either key stroke sequences or menus. The entire user interface is configurable by the user.

The debugger is supported by the Helios C Compiler and Meiko FORTRAN. Uni-processor users will also find the debugger a fascinating tool and a great teaching aid. The Helios Source Debugger provides unique facilities for debugging multi-processor systems and is highly recommended for all Helios programmers and software developers.

Source Debugger

All debugging is done using high level source code objects, the debugger opens a source window for every Helios task. The programmer can then step through this source code, evaluating expressions and variables, displaying structures and tracing the program flow.

Debugging Distributed Programs

Programs running simultaneously on multiple processors can be readily debugged using the multiple source windows. Tasks can be individually single-stepped, traced or run to breakpoints in order to examine the interaction of multiple tasks. Only those tasks which are to be debugged need be run under the debugger, other tasks will continue to run normally.

Debugging multi-threaded tasks

Whenever a new process is created the debugger automatically splits the current source window to show both processes. Each process can then be separately debugged.

Control of program flow

Very flexible control of program flow is provided. One or all tasks may be single stepped or run; breakpoints and watchpoints can be set or a trace run. Single stepping can step through every statement if required, status indicators show when a task is waiting for some event, stack backtracing allows active functions to be monitored or to show from where a function was called.

C expression evaluation

The debugger allows comprehensive evaluation of expressions. All operators are supported, complete type and scope information is available. Any value in a program can be searched for and monitored, structures are displayed in full, pointers can be evaluated to any specified depth.

Command language

The Helios Source Debugger contains a powerful command language. The user can define macros and set command aliases, he can also have direct access to the Helios shell commands.

Configurable user interface

The debugger's user interface is one of its key features, this may reconfigured to suit a user's particular requirements. Multiple windows are used to debug tasks that are running in parallel. Debugger commands may either be invoked as a sequence of key strokes or by selection from the built in menus, the menus allow both debugger and Helios commands to be run.

Separate process for debugger

The Helios Source Debugger is a Helios server so it can be run on a separate processor from the programs which are being debugged if required.

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