[acdha]

I agree with the general point that you could prove such a simple program correct relatively easily but that does still have a cost, which is always a concern in an open-source project. You still need someone to step up and do that work and continue to verify it periodically in the future – if that code is doing complicated things with buffering, that opens up possible odd bugs due to stdlib, gcc, maybe even kernel behaviour changes which might not affect simpler programs.

Not a huge bit of work to be sure but for a non-commercial project you might have trouble finding a volunteer who cares about that tedium.