[openib-general] OpenIB DAT_Return merging and kdat.h

[Tom Duffy]

Caitlin Bestler wrote:

>Given both of those factors, I believe it makes more sense
>to preserve the full DAT_RETURN value (including detail error
>data) as an out parameter. kdat.h could then simply turn it 
>into the functional return for compatability clients and there
>would be no loss of information. Either that or we could work
>out on a case by case basis how kdat.h would be able to restore
>the original error value. This may be possible with data in
>the struct, since multiple outstanding errors on a single 
>object would not seem to be likely (or perhaps more appropriately
>worthy of providing detailed error diagnostics for, since it
>probably represents a totally hosed application).
>  
>

If we decide to add in a compatibility layer with a dat_return 
*parameter, or some other mechanism, this should be a compile time option.

-tduffy