shells/bash port, add a knob which symlinks to /bin/bash ?

[Benjamin Kaduk]

On Fri, 12 Sep 2014, Rang, Anton wrote:

> > If you want interoperability just use /usr/bin/env bash as a shebang.
>
> That doesn't work for this use case -- the user shell coming from LDAP
> -- but I agree that the port shouldn't be modifying /usr/bin.

Here at MIT, where our Athena environment has a long history of providing
a consistent experience across many different platforms, we ended up
limiting the login shells a user could select, to a whitelist we provide
(/bin/sh, /usr/athena/bin/bash, and /usr/athena/bin/tcsh).  (The latter
two are now symlinks to the normal system shells, but they used to be
custom binaries.)

Some people did not like being so restricted, and set their login shell to
/bin/sh, with logic in their dotfiles to re-exec a different shell
depending on the current runtime environment.

-Ben