Software Packager User's Guide

Software integration is a growing area of concern for many programmers and software managers because the need to build new programs quickly from existing components is greater than ever. This includes building versions of software products for multiple hardware platforms and operating systems, building programs from components written in different languages, and building systems from components that must execute on different machines in a distributed network. The goal of software integration is to make building new programs from existing components more seamless --programmers should pay minimal attention to the underlying configuration issues involved. Libraries of reusable components and classes are important tools but only partial solutions to software development problems. Even though software components may have compatible interfaces, there may be other reasons, such as differences between execution environments, why they cannot be integrated. Often, components must be adapted or reimplemented to fit into another application because of implementation differences --they are implemented in different programming languages, dependent on different operating system resources, or must execute on different physical machines. The software packager is a tool that allows programmers to deal with interfaces between software components and ignore complex integration details. The packager takes modular descriptions of the structure of a software system written in the PACKAGE specification language and produces an integration program in the form of a MAKEFILE. If complex integration tools are needed to integrate a set of components, such as remote procedure call stubs, their use is implied by the packager automatically and stub generation tools are invoked in the corresponding MAKEFILE. The programmer deals only with the components themselves and not the details of how to build the system on any given platform. 1Supported by the Advanced Research Projects Agency Grant MDA 972-91-J-1022, the National Aeronautics and Space Administration Grant NAG 5-2129, and the National Library of Medicine Grant N01-LM-3-3525.