Internal Dispatch Table Architecture

This document describes the architecture and details of the netCDF internal dispatch mechanism.

The idea is that when a user opens or creates a netcdf file, a specific dispatch table is chosen. Subsequent netcdf API calls are then channeled through that dispatch table to the appropriate function for implementing that API call.

At least the following dispatch tables are supported.

• netcdf classic files (netcdf-3)
• netcdf enhanced files (netcdf-4)
• OPeNDAP to netcdf-3
• OPeNDAP to netcdf-4

Internal Dispatch Tables

• Adding a New Dispatch Table
• Dispatch Programming Notes
• Accessing Data with put_vara() and get_vara()
• Accessing Attributes with put_attr() and get_attr()

The dispatch table represents a distillation of the netcdf API down to a minimal set of internal operations. The format of the dispatch table is defined in the file libdispatch/ncdispatch.h. Every new dispatch table must define this minimal set of operations.