Out of pty's

[Malcolm Kay]

On Sun, 7 Dec 2003 14:42, Justin Burke wrote:
> * Malcolm Kay (malcolm.kay at internode.on.net) wrote:
> > >     1. Build and install a new kernel with the line
> > >
> > >  pseudo-device pty 256
> > >
> > >        in the configuration file.
> > >
> > >     2. Run the commands
> >
> > I believe this may be out of date. I think the kernel may now
> > produce 256 by default -- I'm on 4.7-STABLE and more than 32 exist for
> > me.
>
> More than 32 may exist, but can you actually use them? 96 ptys currently
> exist on my system, but I can only use 32. The pseudo-device line in my
> kernel is the default (ie.  no numeric value is provided).
>

There is also no numeric value in the relevant line of my kernel config.

I would think that if you can't use ptys they don't exist -- but you might 
still have references to non-existing ptys in /dev/

Are they listed in /etc/ttys? -- apparently this is needed for some 
applications to know they exist.

My check for real existance of ptyq0/ttyq0 was to enter
# cat /dev/ttyq0
in one console window and
# echo fred > /dev/ptyq0
in another.
'fred' then appears in the first window and both commands complete.

I would have thought this was pretty strong evidence that at least this 
master/slave pair actually existed.

(I understand that xterm will not find all 256 ptys -- apparently some 
limitation in xterm -- but should be able to find at least 64.)


Malcolm Kay