2017-02-18 0:46 GMT+09:00 Thor Lancelot Simon <[email protected]>: >> but I said earlier, Memory will not be negaive value. why sysctl use >> singned int? > > Because the sysctl MIB is a public API (and ABI) and it was a signed int > in 4.4BSD. Applicattions are entitled to make assumptions about the > possible range of the returned value, and we are not entitled to invalidate > those assumptions. That's what "compatibility" means. Sometimes you are > stuck with mistakes people made decades ago. > > We did consider making exactly this change about 20 years ago, and concluded > the safe thing to do was to create hw.physmem64 instead.
ok. thanks. I did not know that such circumstances existed. By accumulating history, BSD has been maintained. I will try to understand little by little. -- miwarin
