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<== Date ==> <== Thread ==>

Subject: Re: Logical Naming of Hardware Addresses
From: mcgehee@noao.edu
Date: Wed, 25 May 1994 07:38:09 -0700
Chip writes:
> Proliferation of files is a bad idea.  If you have enough reflective memory,
> you could use dynamic allocation, and include a hash table in the reflective
> memory to look up names.  All IOC's would first look up the name, and if it
> did not exist, would add it dynamically.  A semaphore (soft or hard, depending
> upon what the hardware supports) would protect the hash table.

I would agree that 'profileration' of files is a bad idea but there seem to 
cases in which it is practical for the IOC-based records to interact with
the host via the filesystem.

Current cases include:
	The reading of a JEDEC fuse map during PAL record initialization.
	The writing of image data files by the EPICS Video system.

In the case of complex record types at what point does the number (or desired
run-time flexibility) of the fields really beg for a configuration file to
exist somewhere (host disk, local disk, NVRAM, whatever)?

Peregrine

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