>> No, it returns with success.  I just re-ran with:
>
> In your code, it is not checked, so you can't know that it returned with 
> success.  If the code you are actually running is different, please post 
> that code.  Otherwise, you must check the return value of open, you 
> can't just assume it is correct.

Seth, the sample code is a mock-up of what was causing me problems from my 
original codebase - namely, EINVAL at read.  I duplicated only the 
problem-causing code and the steps required to get there (originally in 
effort to clarify the problem), then removed all ancillary error-checking 
for newspost-ready brevity.

I can re-post the sample code with full error-checking but it does not 
change the results (Invalid argument, meh).

Thanks,
   Kristaps