1 Introduction

The Starlink Software Collection provides an infrastructure of facilities likely to be required by any astronomical application package. The Starlink Software Environment (ADAM) is a particular way of combining the elements of the collection to provide an integrated system with a common look and feel across various packages. Originally developed for VMS at ROE, the system is now supported by Starlink and has been ported to Unix.

Normal data analysis programs for the Starlink Environment are known as A-tasks and it is possible to combine many A-tasks into a single monolithic executable file (an A-task monolith) for efficiency – the tasks may still be invoked separately. The Environment also supports programs for instrumentation control. These need to behave differently from A-tasks and are known as I-tasks,

Programs written for the Starlink Software Environment may be run directly from a Unix shell or from a variety of other user-interfaces including the original ADAM user-interface, ICL (see SG/5), and IRAF cl (see SUN/217).

The first five sections of this document are relevant for any user but the remaining sections will only be of interest to people writing software to run in the environment. For an introduction to these topics and details of how to write ADAM programs, see SG/4 for A-tasks and SUN/134 for I-tasks.

Fine detail about methods of controlling the behaviour of ADAM programs and ICL using environment variables is also given in the appendices.