摘要:

AbstractThe package DBDEBUG assits the users of CODASYL (network) database management systems in two ways. It can be used by applications programmers to debug their programs, and by the database administrator to monitor the performance of the database. The user may select the sections (or even individual statements) of his program to be traced and/or monitored. He may list the specific records and items he wishes to be investigated; he may also restrict tracing and monitoring to only certain DML verbs.The user's database schema and subschema are submitted to processors which generate a data dictionary. This data dictionary is then used by DBDEBUG in modifying the user's DML source code in order to obtain the specified tracing or performance statistics. The output is high‐level in that it reflects the high‐level language (DML COBOL) in which the user's source code was written.The package is designed to be portable. All but one of its components are written in standard Pascal or ANSI COBOL; assembler code is restricted to a ten‐line subroutine which obtains L/O and CPU times from the operating s

ISSN:0038-0644    

DOI:10.1002/spe.4380150602

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

摘要:

AbstractThis 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 theprobe 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 error

ISSN:0038-0644    

DOI:10.1002/spe.4380150603

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

摘要:

AbstractTypes in programming languages cannot model many properties of real world objects and quantities. Consequently, many errors resulting from the inconsistent usage of program objects representing real world objects and quantities cannot be detected automatically. For example, the real variables PRICE and WEIGHT, representing the price of diesel fuel and the weight of a person, may be inadvertently added, giving a non‐sensical value; such an error cannot be detected by a compiler. The programming language Ada introduces the concept ofderivedtypes to tackle this problem. An alternative solution to this problem is the incorporation ofunits of measureas a new data attribute. Derived types only partially solve the problem of detecting the inconsistent usage of objects; some valid usages of objects are also not allowed. Moreover, the solution is inelegant and inconvenient to use. On the other hand, specification of units of measure solves the problem elegantly and conveniently. The two solutions are compared and analysed. Several ways to implement units of measure in Ada are examine

ISSN:0038-0644    

DOI:10.1002/spe.4380150604

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

摘要:

AbstractUNIX has become widely accepted as an efficient, highly flexible operating system for a wide range of computers. It is viewed as being portable because much of it is written in a high‐level language, but transporting it to machines other than its original host is not a trivial procedure. This paper describes the design decisions necessary in moving UNIX to the Data General Eclipse range of minicomputers, and some of the difficulties that arose because of the limited address space on these processor

ISSN:0038-0644    

DOI:10.1002/spe.4380150605

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

摘要:

AbstractProgram design languages are an increasingly important method of expressing the detailed design of a software system. Such languages can be modelled using a data structure known as a semantic net. This paper describes a maintenance tool for program design languages based on such a data structure. The tool allows the user to interrogate a semantic net using an interactive procedural language in order to derive information necessary for software maintenance. The technique upon which this tool is based is applicable to the maintenance of activities throughout the software lifecycle.

ISSN:0038-0644    

DOI:10.1002/spe.4380150606

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

摘要:

AbstractThis paper describes a joint implementation of the LISP and PROLOG languages (with the emphasis in this paper on the latter) for the PRIME range of mini‐computers. Both languages may be compiled or interpreted as required. Several novel techniques for PROLOG compilation are discusse

ISSN:0038-0644    

DOI:10.1002/spe.4380150607

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

摘要:

AbstractA system has been implemented that enables students on a programming course to hand in programs for assessment without the need for printed listings to be generated. The system test runs all submitted programs using standard sets of data, and then facilitates the marking of these programs by the staff teaching the course. The implementation of this system is described, and the experience gained from using it is discussed.

ISSN:0038-0644    

DOI:10.1002/spe.4380150608

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380150609

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY

ISSN:0038-0644    

DOI:10.1002/spe.4380150601

出版商:John Wiley&Sons, Ltd.    

年代:1985

数据来源: WILEY