On Linux at least, the relevant API for reading this sort of data is... open up specific files in /proc and parse the often poorly-documented textual output to

On Linux at least, the relevant API for reading this sort of data is... open up specific files in /proc and parse the often poorly-documented textual output to get the information you need. Which happens to be the kind of thing that C/C++ don't do very well at all, at least in comparison to languages like Python. Although I think Linux is the outlier in this regard.