B Portability

B.1 Overview

This section discusses the portability of SNX, including the coding standard adopted and a list of those Starlink packages which need to be ported to the target machine before a port of SNX can proceed.

B.2 Coding and porting prerequisites

The standard of Fortran used for the coding of SNX is fundamentally Fortran 77, using the Starlink Fortran coding conventions described in SGP/16. Several common extensions to the Fortran 77 standard are used in the SNX source code; they are as follows:

• symbolic subprogram names may be longer than six characters (but are always shorter than ten characters);
• symbolic subprogram names include the “_” symbol;
• the full ASCII character set is assumed in character constants.

There are no operating system-specific routines in SNX. SNX requires NCAR, SGS and GKS Vn. 7.2 or GKS Vn. 7.4 to be available.