A high-level debugger for PL/I,Fortran and Basic

Dartmouth College has implemented a single debugger for several languages sharing a common runtime environment: PL/I, Basic and Fortran. The debugger is fairly powerful; users set breakpoints and traces which occur whenever the values of given variables change, or whenever certain relational expressions become true, for example. All debugging is carried on in a syntax similar to that of a high-level language. This debugger was implemented in about a month. It should be fairly easy to implement on most timesharing systems. This paper describes the debugger's user interface and gives a rough sketch of its implementation.     

Debugging mixed‐environment programs with Blink

Programmers build large‐scale systems with multiple languages to leverage legacy code and languages best suited to their problems. For instance, the same program may use Java for ease of programming and C to interface with the operating system. These programs pose significant debugging challenges, because programmers need to understand and control code across languages, which often execute in different environments. Unfortunately, traditional multilingual debuggers require a single execution environment. This paper presents a novel composition approach to building portable mixed‐environment debuggers, in which an intermediate agent interposes on language transitions, controlling and reusing single‐environment debuggers. We implement debugger composition in Blink, a debugger for Java, C, and the Jeannie programming language. We show that Blink is (i) simple: it requires modest amounts of new code; (ii) portable: it supports multiple Java virtual machines, C compilers, operating systems, and component debuggers; and (iii) powerful: composition eases debugging, while supporting new mixed‐language expression evaluation and Java native interface bug diagnostics. To demonstrate the generality of interposition, we build prototypes and demonstrate debugger language transitions with C for five of six other languages (Caml, Common Lisp, C#, Perl 5, Python, and Ruby) without modifications to their debuggers. Using real‐world case studies, we show that diagnosing language interface errors require prior single‐environment debuggers to restart execution multiple times, whereas Blink directly diagnoses them with one execution. Copyright © 2014 John Wiley & Sons, Ltd.     

Retargetability and Extensibility in a Parallel Debugger

This paper describes the design and implementation ofPanorama, a parallel debugger for MIMD message-passing computers. Programmers can readily adapt Panorama to new parallel platforms and extended it to include their ownviewsof a target program. The system comes with three built-in graphical program views, and it also includes a software tool to help programmers design and implement new views. Panorama avoids detailed dependence on target architectures by using thebase debuggersupplied by each hardware vendor to carry out low-level debugging tasks such as setting breakpoints and examining data. Since the interfaces and capabilities of base debuggers vary, we have developed a strategy that models interactions between Panorama and base debuggers. The model separates general-purpose code from the special-case functions that handle specific debugger characteristics. The resulting system is easy to adapt and free from the clutter of conditionally-executed, special-case code.     

开源跨平台的图像可视化调试器设计

目的 在调试C/C++图像处理程序时,如何以可视化的形式观察被调试程序中的图像变量,对于调试过程尤为关键。目前尚未有跨多操作系统平台的图像可视化调试器可供使用,该款开源跨平台的图像可视化调试器的设计与实现弥补了此领域的不足。方法 利用GDB(GNU debugger)调试器的Python接口,将被调试程序中的图像变量对应的内存字节序列转化成Python下的2维数组,并采用Matplotlib库加以显示,整个图像显示线程独立于GDB的文本字符交互主线程。结果 在Windows、Linux、Mac系统中分别进行实验,均可实现图像变量的显示、缩放、平移、像素数值查看、保存等多种功能,并使得GDB的命令行保持非阻塞模式运行。结论 开源跨平台的图像可视化调试器的设计,满足了不同操作系统平台下图像程序的开发调试需求,弥补了当前GDB调试图像程序功能的不足,提高了图像处理程序的开发和调试效率。     

NCFW专家系统的汉语接口

NCFW系统是适合于花岗岩与变质岩地区的勘探地下水专家系统，系统的人机交互既可用菜单（亦称项目单）方式，亦可用汉语对话方式。这两种方式既可混合使用亦能灵活切换。本文着重描述了汉语接口的设计思想、实现中采用关键技术以及系统运行实例。     

A debugger for concurrent programs

This paper reports on an experimental debugger for concurrent programs. Design objectives include a showing of greatest usefulness when dealing with multiprocess interactions, creation of a simplified more approachable interface for programmers, allowance for the systematic organization (and limitation) of debugging information by programmers, reflection of a natural view of concurrency, and portability. The design responds to a perceived need for debugging techniques applicable in systems of concurrent, communicating, asynchronous processes. During debugging sessions, a user is able to dynamically explore interprocess synchronization points, parallel actions and deadlock situations. The programmer interface is based on a transparent window multiplexer providing a set of windows for each concurrent process. The window manager interactively maps interesting windows to programmer-specified viewscreen locations, while relegating temporarily uninteresting windows to the background. In implementing a debugger for concurrent programs, a principal concern is the probe effect, or the possibility that the debugger itself masks synchronization errors in the program being debugged. For the examples explored, the probe effect was not observed to limit the localization of implanted synchronization errors.     

A debugger for parallel processes

A system for analysing and debugging parallel Fortran codes is in use on the Sun workstation. The system is composed of a parallel processing simulator mtsim, a window- and mouse-based debugging tool mtdbx, and a set of real-time display routines. The simulator mtsim, which is called from Fortran by a set of routines having the same syntax as the CRAY X-MP multitasking library, causes several concurrently active user tasks to be executed. The debugger mtdbx is based on the Sun dbxtool debugging facility. It has an enhanced command interface with functional control of parallel processes in multiple windows. The display routines offer two real-time views of multitasking synchronization primitives as they are used during execution. These three components of the debugging system afford the opportunity to analyse the behaviour of parallel processes by dynamic interaction at run-time.     

Dynamic Query-Based Debugging of Object-Oriented Programs

Program errors are hard to find because of the cause-effect gap between the instant when an error occurs and when the error becomes apparent to the programmer. Although debugging techniques such as conditional and data breakpoints help in finding errors in simple cases, they fail to effectively bridge the cause-effect gap in many situations. This paper proposes two debuggers that provide programmers with an instant error alert by continuously checking inter-object relationships while the debugged program is running. We call such tool a dynamic query-based debugger. To speed up dynamic query evaluation, our debugger implemented in portable Java uses a combination of program instrumentation, load-time code generation, query optimization, and incremental reevaluation. Experiments and a query cost model show that selection queries are efficient in most cases, while more costly join queries are practical when query evaluations are infrequent or query domains are small. To enable query-based debugging in the middle of program execution in a portable way, our debugger performs efficient Java class file instrumentation. We call such debugger an on-the-fly debugger. Though the on-the-fly debugger has a higher overhead than a dynamic query-based debugger, it offers additional interactive power and flexibility while maintaining complete portability.     

A Machine-Independent Debugger

cdb is a simpe, source-level debugger for ANSI/ISO C programs compiled by lcc, a retargetable C compiler. cdb is completely independent of its target architecture. This independence is achieved by embedding a small amount of itself — a nub — in the program to be debugged and by having the compiler emit machine-independent symbol-table data and related code. This paper describes the design of a nub interface for debugging, a target-independent implementation of this interface for cdb, and the implementation of cdb itself. When compared to platform-specific debuggers, cdb's implementation is minuscule: the nub, debugger, and associated communications routines take about 1500 lines of C, and fewer than 600 lines were added to lcc's front end to emit symbol tables and breakpoint hooks. All this code is machine independent.     

Ergonomic evaluation of interaction techniques and 3D menus for the practical design of 3D stereoscopic displays

There has been a recent commercialization of 3D stereoscopic displays in order to implement them in a virtual reality environment. However, there is a lack of extensive research into user interfaces for 3D applications on stereoscopic display. This study focused on three representative interaction techniques (ray-casting, keypad and hand-motion techniques) utilizing a head-mounted display and 3D CAVE. In addition, the compatibility with 3D menus was also investigated based on performance and subjective assessment. Nine 3D menus were designed for the experiment in regards to three 2D metaphors (pop-up, pull-down and stack menus) and three structural layouts (list, cubic and circular menus). The most suitable technique for the 3D user interface on a stereoscopic display was the ray-casting technique and the stack menu which provided the user with good performance and subjective response. In addition, it was found that the cubic menu was not as effective as other menus when used with the three interaction techniques.Relevance to industryThis research describes a distinctive evaluation method and recommendations that guarantee the suitability for interactive 3D environments. Therefore, the results will encourage practitioners and researchers that are new to the area of 3D interface design.     

ANTLRWorks: an ANTLR grammar development environment

Programmers tend to avoid using language tools, resorting to ad hoc methods, because tools can be hard to use, their parsing strategies can be difficult to understand and debug, and their generated parsers can be opaque black‐boxes. In particular, there are two very common difficulties encountered by grammar developers: understanding why a grammar fragment results in a parser non‐determinism and determining why a generated parser incorrectly interprets an input sentence. This paper describes ANTLRWorks, a complete development environment for ANTLR grammars that attempts to resolve these difficulties and, in general, make grammar development more accessible to the average programmer. The main components are a grammar editor with refactoring and navigation features, a grammar interpreter, and a domain‐specific grammar debugger. ANTLRWorks' primary contributions are a parser non‐determinism visualizer based on syntax diagrams and a time‐traveling debugger that pays special attention to parser decision‐making by visualizing lookahead usage and speculative parsing during backtracking. Copyright © 2008 John Wiley & Sons, Ltd.     

Using HCA and TOPSIS approaches in personal digital assistant menu–icon interface design

Mobile electronic products have recently become very popular because of their portable convenience and versatile functions. The personal digital assistant (PDA) can even access the Internet. However, there is still plenty of room for improvement in the PDA interface. This research proposes a systematic approach to analyze, generate and evaluate a PDA integrated menu–icon interface design for the DigitHub Company based on customer requirements.Hierarchical clustering analysis (HCA) is incorporated with the analytic hierarchy process (AHP) to identify and categorize functional PDA menus and their corresponding icons. We evaluate the importance of each of the different functional menus and categories. We generate five PDA menu–icon interface design alternatives that meet the proposed design guidelines, and we evaluate each for their respective feasibilities. The technique for order preference by similarity to ideal solution (TOPSIS) method is applied to measure the overall operating performance of the five PDA menu–icon interface design alternatives. The evaluation results show that the preferred design is option PDA₅, a hierarchical and separated menu–icon layout style that features a two-layer menu structure.We expect that the proposed development procedure for the generation and evaluation of PDA menu–icon design alternatives based on customer requirements will be of interest to interface designers who wish to focus on mobile products.

Relevance to industry

This paper proposes an integrated procedure for designing PDA menu–icon interfaces. Our methodology should help in the creation and optimization of screen layouts for mobile phones, global positioning system (GPS) navigation devices, digital cameras and related screen interfaces.     

CK·CORE嵌入式调试器接口设计

论文提出了一种基于片上仿真方式的调试器的硬件接口设计,为避免扫描链方法的问题,片上仿真模块采用映像寄存器方式实现,为了灵活性和可移植性,调试器软件采用了一种远程代理结构,所有硬件模块和软件模块都在拥有自主知识产权的32位高性能嵌入式CPU芯片CK·CORE配套调试器的设计中实现,并给出了与其他调试方式相比较的实验结果。     

Adding debugging support to the Prometheus methodology

This paper describes a debugger which uses the design artifacts of the Prometheus agent-oriented software engineering methodology to alert the developer testing the system, that a specification has been violated. Detailed information is provided regarding the error which can help the developer in locating its source. Interaction protocols specified during design, are converted to executable Petri net representations. The system can then be monitored at run time to identify situations which do not conform to specified protocols. A process for monitoring aspects of plan selection is also described. The paper then describes the Prometheus Design Tool, developed to support the Prometheus methodology, and presents a vision of an integrated development environment providing full life cycle support for the development of agent systems. The initial part of the paper provides a detailed summary of the Prometheus methodology and the artifacts on which the debugger is based.