Maybe a problem in binary read/write (PR#1688)

Hello,

Prof Brian D Ripley wrote:

Not a bug: check the documentation of file(), which is documented to work
for files but not for devices.  No attempt is made to cope with e.g.
blocking on non-files.

It's a pretty extreme view of the world to consider /dev/psaux to be a
file, and R is just using standard C <stdio.h> I/O.

However, this is a great opportunity for you to contribute a device()
function to R.

I finally checked the code and "wrote" the functions to "handle devices".
Well, in fact I more or less duplicated the code for FIFOs, removed the
option for encoding, added an option for synchronous I/O, and added a
test to check that the file is indeed a character or block special file.
This works great for me but I'm afraid it is a bit simple and does not
cover much of device handling in general.  Especially I don't know if
anybody would want to use it for block devices, and what they would need.
The psaux device is one of the simplest device one could think of, that's
why it works so well.  For other devices one would need at least an
ioctl function, which I didn't write.  But still I have no idea whether
anybody would use it and what for.  Anyway.  Please let me know if you
think this is useful.  If yes, I will try to familiarize myself with
the structure of the R code and make the device handling more general.

Thanks,
Johnny