Re: Refactoring / renaming Channel -> Pv

[Benjamin F. <ben...@he...>]

On Monday, November 25, 2013 20:48:59 Dalesio, Leo wrote:
> Channel is what cav3 delivers.
> PV is what pvaccess delivers.

I think it is a very bad idea to chose names in this way!

Name should reflect function. Thus:

Process Variable (PV):
        A named entry point to some (possibly remote) service, visible and
        accessible across a network.

Channel:
        An interface providing access a PV, possibly (but not necessarily)
        using some network protocol.

This should be independent of whether we talk about CA or PVA.

The names "Channel Access" and "PV Access" should be regarded as an
exception to the above rule. They do *not* reflect functionality.
Rather, they exist to distinguish between two definitions and
implementations of network protocols that provide access to PVs via
Channels:

PV Access:
        A network protocol and its implementation providing access to PVs
        via Channels.

Channel Access (CA):
        Another network protocol and its implementation providing access to
        PVs via Channels.

PV Access and Channel Access differ in the functionality they offer. PV
Access is strictly more powerful, it has a wider range of data types and
services, and can be used to emulate and/or replace Channel Access.

Cheers
Ben


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