Subject: Re: Linux pseudo pty
To: Andrew Brown <>
From: Todd Vierling <>
List: tech-kern
Date: 02/25/2001 16:27:53
On Sun, 25 Feb 2001, Andrew Brown wrote:

: >Solaris, for instance, provides BSD-style (SunOS 4 compatibility) ptys named
: >/dev/[pt]typ[0-9] and so forth, but they aren't in the same device
: >numberspace, because the naming scheme is quite limited.  In the case of
: >/dev/pts having its own device space, you could have as many nodes as you
: >want (or even a kernel fs similar to fdesc), without worrying about running
: >out of letters.
: actually, you can run out.  i have, and it's a strange failure mode.

Well, there is a hard limit on the ptmx descriptors, but the point was that
the ptmx devices, while functionally compatible once open()ed, don't have
the much more restricted numberspace caused by using the letter-and-hexdigit
naming scheme of the BSD ptys.

-- Todd Vierling <>  *  Wasabi NetBSD:  Run with it.
-- NetBSD 1.5 now available on CD-ROM  --