Maximum # of Pseudo-Terminals in UNIX

[Gordon C. Galligher]

This question pertains to the maximum number of pseudo-tty's per UNIX
system.  The following is an excerpt of the Berkeley telnetd.c version
5.29 recently found in the uunet archives in bsd-sources:

***	for (c = 'p'; c <= 's'; c++) {
		....
***			line[sizeof("/dev/ptyp") - 1] = "0123456789abcdef"[i];
	.....
	fatal(f, "All network ports in use");

I wanted to know if the 64 ports supported by the telnet daemon is a UNIX
restriction, or if it is the restriction of just the code of the telnet
daemon?  

In the case of a windowing environment (ex: X with X-terminals), 64
pseudo- terminal ports doesn't seem like a whole lot and can get eaten up
pretty quickly.  The SunOS 4.0.1 manual page for pty(4) shows only
pty[p-s][0-9a-f] (same as telnet) for the pseudo terminal controllers and
devices.  If this is a soft-limit, is there a way in the kernel to up this
limit, or are we in for a problem (just like we are in January 19, 2038,
at 03:14:07)?

Since this question has many repercussions I have cross-posted it to all
the newsgroups I feel qualified to answer my question.  Please forgive me
if I have erred in this assumption.

Thank you all very much for any information you can throw my way!

		-- Gordon.

Gordon C. Galligher  <|> ...!uunet!telxon!gorpong <|> gorpong at telxon.uucp.uu.net
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