Experimental Physics and
Industrial Control System

Benjamin Franksen <[email protected]> · Wed, 18 Jun 2014 13:42:14 +0200

On Wednesday, June 18, 2014 10:12:29 Ralph Lange wrote:
> On 18/06/2014 08:43, Torsten Bögershausen wrote:
> > thats sounds too interesting to keep quiet.

Indeed. This is a pretty neat idea.

> Other applications could include refreshing the last n lines of some
> (log) file into a char array, or ......
>
> Windows/Linux line endings would be handled through EOS processing,
> interpose layers could do interesting things.
> An similar (slightly simpler) drvAsynWriteFilePort could allow writing
> to a file (overwriting or appending).
>
> File IO is something that is traditionally hard to do on an IOC - this
> approach might provide an easy way for many use cases.

With the added advantage that the IO (more precisely: the waiting for
the IO completion, as well as parsing into some internal format) is
automatically done in a worker thread i.e. asynchronously.

For the cvtRecord I did something like that w/o using asyn: all records
share a worker thread that is responsible for (re-)loading files and
converting them into an internal data structure, updating the record
only after all the steps have completed successfully. This allows you to
re-load tables during normal (e.g. periodic) operation w/o noticeable
disturbance.

Cheers
Ben
--
"Make it so they have to reboot after every typo." ― Scott Adams

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System