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Date: Tue, 5 Sep 1995 13:33:07 -0700
From: Sean Eric Fagan <sef@kithrup.com>
Message-Id: <199509052033.NAA16940@kithrup.com>
To: hackers@freebsd.org, roberto@keltia.frmug.fr.net
Subject: Re: Change in behaviour of SU...
Sender: hackers-owner@freebsd.org
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>#ifdef KERBEROS
>#include <kerberosIV/des.h>
>#include <kerberosIV/krb.h>
>#include <netdb.h>
>
>#define	ARGSTR	"-Kflm"
>
>int use_kerberos = 1;
>#else
>#define	ARGSTR	"-flm"
>#endif

The "-c" is not an argument to su.  It is an argument to sh.  The original
manpages for su said that any extra arguments would be passed to the
subshell spawned, whatever that was.  The changes I sent to freebsd a long
time ago did that; those changes were checked in.

When you say "su root -c ls" you are saying, "as root, do '/bin/csh -c ls'".
If you say "su root exit", you are saying, "as root, do '/bin/sh exit'".

Sean.