How to read a 1-wire sensor with C on a Raspberry Pi

[Kevin Cozens]

On 14-01-16 07:55 PM, Jamon Camisso wrote:
> Second, I'm not sure how to extract the t=17625 value - it is always at
> position len-6 (\0 line termination needs to be accounted for). It is
> always the same length which is great. But:
>
> Question 2) Is there a better way than strncpy?

FYI, in your original (as pasted), you declared temp_raw as a char array 
with space for five characters but your strncpy was reading in up to 6 
characters. The temp_raw buffer should have been big enough to hold the 
maximum number of characters. strncpy could read up to 6 characters so 
temp_raw should be declared with 7 minimum (up to 6 from strncpy, plus space 
for a terminating NUL).

Avoiding strncpy:

   float raw_temp;
   sscanf(&line[len-6], "%f", &raw_temp);
   float temp_f = floorf((raw_temp/1000 + 0.05)*100)/100;

-- 
Cheers!

Kevin.

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