Bug#256468: xterm: utmp handling is broken for high pts

[Jim Paris <jim@jtan.com>]

> > Is it your opinion that this is a bug in the Linux kernel, then?
> 
> neither - I did read that this behavior is changed in the next version
> of the kernel, but it's something that xterm should (in principle) handle.
> 
> But if it's really changed as reported, then I may not have to fix anything.

If the Linux kernel behavior reverts to reusing PTYs, that just means
that pty numbers greather than 1000 will be unlikely, but they can
still show up on systems where e.g. more than 1000 users are logged
in.  So the bug should probably be fixed anyway.

The problem is really with the fact that ut_id is so short, so this
may be something that e.g. the glibc people could fix too.

-jim