su 5.2.1 does not invoke bash as a login shell when stdin is from a

That is precisely correct.

However, I have not been able to reproduce your results. I havesufrom the coreutils-5.2.1 package (distributed with Slackware, but it is from the FSF's GNU project).

Note that "-", "-l" and "--login" are all exactly the same option. Regardless, the above command probably does *not* do what the poster thought it does. It will attempt to execute a command named "foo", as the root user and from a login shell. It will of course fail if there is no "foo" command... :-)

If that works for the poster, then clearly thesuused is *not* the samesuthat comes with coreutils-5.2.1. There are many variations ofsuavailable.

I can't reproduce your problem. It does not appear to be ansuproblem, and must be something else. What is the login shell listed for your "usr1" inetc-pbuttwd? And what shell are you running when you executesu-.

Note thatsuinvokes a "login shell" by prepending a '-' to the name. If you run your su command and then do "echo $0" you will see what shell it is invoking, and if it is in fact invoked with the '-' or not. If what you see is "bash", then there is a problem withsu-, but if what you see is "-bash", then your version of "bash" is at fault. (Subsbreastute whatever you get for "bash".)

Also, can you verify yoursu-? You showed, if I remember right, something like "su --version", and the source code from coreutils-5.2.1 does not have such an option. Do we have the samesu-????

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