SPP Reference Manual

Preface

The Subset Preprocessor Language (SPP) is a programming language designed to develop applications in the IRAF programming environment. This is a reference manual intended to explain the language sufficiently to allow a programmer to develop useful applications. As such, it comprises two fundamental parts. The first is a detailed reference describing the lan- guage's features, syntax, and structure. The other is a fairly complete description of the interfaces to the IRAF environment. Separate chapters are devoted to error handling and making IRAF tasks. Four appendixes cover the system defined include files, detailed examples and other helpful hints, and utilities for debugging applications code. Appendix E describest the STSDAS tables utilities. Simple examples of specific concepts are scattered throughout this text. These are usually fragments of code intended to illustrate the concept under discussion. However, Appendix B contains a few complete examples.

This is not a programming textbook. It is assumed that the reader is con- versant with some programming language. Because of the similarity of SPP to Fortran and C, experience with those languages is certainly an asset. It is also assumed that the reader is familiar with IRAF to some extent. That is, that there is some experience with the concepts behind the structure of programs and rationale for the system. In addition, some knowledge of the IRAF command language (cl) is assumed.

Some comments on the syntax in this text may be useful.

Literal text and reserved keywords to be used in code as-is are set in typewriter style to distinguish them from names of objects and real English words. For example, procedure, pointer, or maxch are keywords that may be used in SPP code. Another example is a directory or file name, which, as literal text, would be set in typewriter style: gio$doc/gio.hlp or help cursor.
When a reserved word ends in an italicized capital T, the T is a place-holder intended to be replaced by a data type character. These data type specifiers include:
- x - Complex
- d - Double
- l - Long
- s - String
- c - Char
Package names are set in bold face, for example, cl or imio.
Generic names for entities replaced by some specific keyword are set in italic style, such as a template syntax: for (init; test; control) demonstrating the for syntax.
Square brackets used in a template ([ ... ]) surround optional text.
Function names are usually referred to in the text without arguments but with empty parentheses to distinguish them from other identifiers.

SPP is a part of the IRAF application environment. IRAF was devel- oped by the National Optical Astronomy Observatories (NOAO), primarily for the analysis of astronomical data. Doug Tody is primarily responsible for the design and management of the IRAF core system, including SPP. Additional examples of how to develop IRAF applications code can be found in An Introductory User's Guide to IRAF SPP Programming by R. Seaman [Seaman92].

Chapter 1 of this manual is based largely on Doug Tody's A Reference Manual for the IRAF Subset Preprocessor [Tody83]. Chapter 2 draws from the design documents for the various interfaces, and Appendix E is based on earlier document by the STSDAS Group.

Generated with CERN WebMaker