Path: utzoo!utgpu!watserv1!watmath!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!uupsi!vmp!sonyd1.Broadcast.Sony.COM!blilly.UUCP!balilly.UUCP!bruce
From: bruce@balilly.UUCP (Bruce Lilly)
Newsgroups: news.software.b
Subject: Re: NNTP 1.5.10 / Cnews 15-Dec-1990 / Stupid UNIX exec
Message-ID: <1991Jan31.023944.19068@blilly.UUCP>
Date: 31 Jan 91 02:39:44 GMT
References: <1991Jan30.062800.15853@ecst.csuchico.edu>
Sender: news@blilly.UUCP (News Administrator)
Organization: Bruce Lilly, Flushing, NY
Lines: 69

In article <1991Jan30.062800.15853@ecst.csuchico.edu> warlock@ecst.csuchico.edu (John Kennedy) writes:
>
>  I'm setting up a system with these beasties, and I've run into a hurdle
>that someone may have delt with already or have a clever solution to.
>
>  When a remote Pnews batches up an article, it is received by NNTP, tossed
>into a temporary file in /usr/tmp, and it forks/execs inews.  Fine and dandy,
>expect that inews is a shell script and I can't do any sort of an exec() on
>anything but a a.out-format file.  It seems to be happy by execing ksh and
>passing along the arguments to inews for ksh to deal with.  (Seemingly solved
>-- I only mention it because it isn't stock behavior).

I also ran into this, but I don't recall exactly how I solved it.  I'll
just note in passing that one possible solution is contained in the
exec(2) man page -- two members of the exec family will work with scripts
(Hint: read the description of the ENOEXEC error return).

>  Inside inews, our pal anne.jones is called.  Anne decides she must call "who
>am I" for some reason.  (Lack of $USER being set?  What should it be set to?)
>This is EVIL -- who yacks because the user isn't on a terminal and it can't
>find the name.  The decent into darkness has begun.
>
>  It makes two other attempts to find a user's name, and probably with no name
>to look with, either, since the "who" failed.  It looks in /etc/passwd, which
>fails because the machine doesn't have user accounts and then ypmatch, which
>the machine doesn't have at all.
>
>  Burp, regurgitate, error, nothing posted.
>
>  Now:
>	(A)  What is our little Anne trying to look up?  The name that NNTP
>		runs under, or the user's name?

The latter.

>	(B)  Can I just write something to do what "who am i" should?  (If so,
>		I presume it should return the info for (A).)

Here's an excerpt from the anne.jones I use (it works for me, but your
mileage may vary):

# dig up user's name (a simple task, you'd think, but you'd be wrong)
case "$LOGNAME" in
"")
	# "who am i" on many Unixes does "ttyname(0)" and "getpwuid(getuid())"
	# if that fails - it can be confused by empty utmp entries (per jerqs);
	# "who am i </dev/null" yields your userid, not your login name.
	# "tty" does "ttyname(0)"; also fallible.
	# So, emulate a slightly-modified V7 getlogin(3) (actually ttyslot(3)):
	# look for tty on /dev/tty, stdin, stdout, stderr (actually via ttyname(3)).
	for fd in 3 0 1 2			# 3 is /dev/tty on V8
	do
		if test -t $fd; then
			case "$USER" in
			"")	USER="`who am i <&$fd |
				    sed -e 's/[	 ].*//' -e '/!/s/^.*!//' `" ;;
			esac
		fi
	done
	case "$USER" in
	"")	USER="`logname`";;	# last resort: use userid
	esac
	;;
*)	USER="$LOGNAME" ;;


Good luck.
--
	Bruce Lilly		blilly!balilly!bruce@sonyd1.Broadcast.Sony.COM