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CFD General Notation System
CGIO User's Guide

Version 4.2

The CGIO interface provides low-level access to the database manager which underlies CGNS. The original database manager for CGNS was ADF (Advanced Data Format), and as such much of the CGIO interface routines are patterned after this. Starting with CGNS library version 2.xx, a new database manager HDF5 (Hierarchical Data Format) was introduced. At that time only one of these database managers could be used at a time, and this was selected at build time.

In CGNS library version 3.xx, the CGIO interface was developed to support both database managers simultaneously, and in a fashion transparent to the application code. This is now the preferred way to access the database manager.

This document defines the general structure of a database file, but not the specific implementation details. See the ADF and HDF5 Implementations for the details. The CGIO core routines used to store and retrieve data from the database manager are also described.

The complete CGIO Manual in HTML form is also available for installation on a local system. This is a gzip'ed tar file (32K, 143K gunzip'ed), and may be downloaded by clicking on the link while holding down the shift key, assuming your browser supports this capability. A dialogue box will appear for you to specify the directory and file name. To unpack the contents, do

   gunzip -c cgio.tar.gz | tar xvf -
The files will be extracted and stored in the directory cgio. Point your browser to the local file cgio/index.html to display the CGIO Manual home page. Note also that some links, to other manuals, etc., may not work.