.. _cgi_parameter_reference: CGI Parameter Reference ======================= This document catalogs every CGI environment variable that the web forms can send to the three tools (Viewer, Tracker, Ephemeris Generator), with every possible value listed explicitly. It is derived from the SHTML form definitions in ``web/tools/``. When the package is installed via pip, copy those files to a target directory with: ``install_ephemeris_tools_files /path/to/htdocs/tools``. The Perl ``newcgi.pm`` module parses the query string and exports each ``key=value`` pair as an environment variable. The FORTRAN binary (or, now, the Python ``--cgi`` mode) reads these environment variables directly. **PREFIX** is an optional string prepended to CGI environment variable names to distinguish mission-specific forms from Earth-based forms. When the form is for Earth (no mission), PREFIX is empty. Examples of non-empty PREFIX include ``"Cassini"`` and ``"JUICE/"``; variables then appear as ``PREFIXvariable`` or ``PREFIX/variable`` depending on usage. The ``newcgi.pm`` module sets these environment variables; the Viewer, Tracker, and Ephemeris Generator tools read them. Conditional parameter availability and possible values throughout this document depend on whether PREFIX is empty or set (e.g. ``xunit`` and body lists). .. contents:: Table of Contents :local: :depth: 2 General Notes ------------- Whitespace in ``