On Wednesday 30 September 2009 11:30:26 Benjamin Franksen wrote:
... several wise words, including:
> It /is/ a difference to the server whether you request DBR_SHORT, DBR_INT,
> or DBR_LONG. These will trigger different conversion routines, and thus
> might give different results.
I should add that the request type also affects the amount of data passing
over the wire; if you request a large image with 8-bit pixels as a DBF_LONG or
worse a DBF_DOUBLE array, you're going to be wasting network bandwidth and CPU
time on the IOC converting all those individual 8-bit values into larger
quantities. Much better to do that conversion on the client.
I would encourage those working on this to read the release notes for R3.14.11
as there are a couple of things we added which you guys are going to want to
provide support for:
* Long strings. Important for accessing DBF_xxLINK fields since record names
can be up to 60 characters long, so you can't always read or change the value
of a link field using a 40 character DBF_STRING.
* DBE_PROPERTY events. Generated now on the VAL field of the mbb[io] record
types when someone changes one of the *ST fields, a DBE_PROPERTY monitor
allows a client to always know what the current ENUM strings are.
- Andrew
--
The best FOSS code is written to be read by other humans -- Harald Welte
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