Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!ucsd!rutgers!cmcl2!phri!marob!daveh
From: daveh@marob.MASA.COM (Dave Hammond)
Newsgroups: comp.unix.xenix
Subject: Re: SCO Xenix System Hang
Message-ID: <418@marob.MASA.COM>
Date: 14 Dec 88 17:17:02 GMT
References: <766@wasatch.UUCP> <329@bilver.UUCP>
Reply-To: daveh@marob.masa.com (Dave Hammond)
Organization: ESCC  New York City
Lines: 32

>In article <329@bilver.UUCP> bill@bilver.UUCP (bill vermillion) writes:
>We are having problems with SCO 386 Xenix and are looking for some help.
>[...]
>         .  When a user runs our software, they all login with the
>same user id which starts executing our own user interface shell
 ^^^^^^^^^^^^
 (problem lies here)

>hang is interesting.  If you have a terminal sitting at the regular sh
>prompt, you can type carriage returns and the prompt is echoed.  If
>you do any command (ps, shutdown, etc) then it just goes away and
>doesn't respond.  You can still type on the terminal, characters are
>echoed, but nothing happens.  You can also switch to a different
>screen and bring up the system prompt.  However, if you try to type on
>this screen, nothing is echoed.

You have exceeded the system-imposed open files limit (_NFILES in stdio.h)
for a single user-id.  The only solution is to assign individual user
accounts to each of your users.

The shell prompt will continue to be issued, as no files are opened by
simply pressing Return.  However, as soon as a valid (non-builtin) command
is issued, the shell must fork/exec the child program, which involves
opening more files (the program binary itself, at the very least) and
fails due to the afore-mentioned file table overflow.

BTW, unless there is a Real Good Reason for having multiple users with the
same user-id, it is far more appropriate for security, file management and
system administration purposes to assign individual user-ids.

--
Dave Hammond
...!uunet!masa.com!{marob,dsix2}!daveh