2 Introduction

The JCMT uses the GSD file format for its current heterodyne acquisition system (via the Dutch Autocorrelation Spectrometer (DAS)) and for its archive of pre-SCUBA data. This document describes the C version of the GSD library (a FORTRAN interface is layered on top), now distributed as a standalone package and not part of an application. The current library cannot be used for creating or modifying GSD files.