[phobos] UnbufferedFile, or, abstracting the File ranges

[Andrei Alexandrescu]

Steve Schveighoffer wrote:
> Re: byLine and byChunk, I don't think these are a good idea on 
> unbuffered files.

byLine is onerous because it reads one character at a time, but byChunk 
makes a lot of sense. It essentially is buffering straight in user's 
buffers. A lot of Unix utilities do that.

> For example, your current implementation will be extremely slow.  
> Reading one char at a time is OK on a buffered file, because most times 
> its just a simple fetch of a char from a buffer.  But your 
> implementation reads a single character at a time from the actual file 
> on disk, a very slow operation.
> 
> I think unbuffered files are good for when you want to handle the 
> buffering yourself, or when you want to pass them to child processes.

Actually a great use case is character-level unbuffered files when you 
want to do something for each keypress off a tty.


Andrei