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Re: [RFC/Patch] What about using seekoff(-1, ...) for unbufferedunderflow?
>Well, seeking after every _unbuffered getc()_ (vs. buffered and/or sbumpc)!
Right. This is sub-optimal, considering pback can be used. I don't think
you disagree about this part, actually.
>On the other hand, an heavier sbumpc() affects any sbumpc(), buffered or not
>and I think that, for top performance, people really want a fast unbuffered
>sbumpc().
I'm sympathetic to your purity test on _M_buf_size, but I think your
proposed cure is worse than the disease...
> Also, the underflow call should be checked for its return value.
I'm not convinced of this either. ;)
If this branch is taken, __ret is unchanged regardless of what underflow
returns. If underflow returns eof, then getc will return this on next
input.
Perhaps I'm wrong: if so, show me.
-benjamin