> From: "Theo de Raadt" <dera...@openbsd.org> > Date: Wed, 26 Jul 2017 08:07:53 -0600 > > > The current behaviour of our implementation is to return the number > > of characters printed *and* set errno = ENOMEM. > > I expect it should not set errno. As a general rule, errno should > only be set if an error has been indicated. Other short operations > don't set errno.
POSIX says: "The value of errno should only be examined when it is indicated to be valid by a function's return value." So clobbering errno when not returning a negative number is allowed. The real question here is if we should report (partial) success if we encounter an error halfway through printing/formatting.
