I discovered a problem when accessing the Analog pins on the BBB.

Whenever I would read the value of the pins, I needed to read a second time 
to get the correct value. This is because the first file read initiates the 
conversion, and the second gets the actual value. I found that if I did the 
read back to back, with no delay in between, the second read would fail by 
way of a buffer underflow (reading the file using the ifstream class in 
C++). I am assuming this happens because the conversion is not complete, 
and as such there is no data yet.

My question is this: Is there a way to check if the conversion is done 
before attempting the read? I need these reads to happen pretty quick, so I 
cant afford to burn 50ms before the second read, and if I try to read them 
too much quicker than that, I get an occasional seg fault from the 
underflow.

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