Scott Robbins wrote:
On Tue, Apr 26, 2016 at 07:27:26PM -0700, Alice Wonder wrote:
Some of the BSDs use to have a bourne shell and maybe some do, I don't
know.
Yup.
bash is mostly compatible with bourne (can run most bourne scripts)
which is why /bin/sh is a symlink to /bin/bash on GNU and most other *nix systems.
Bash can run Bourne, but not necessarily vice versa, which can be
problematic if, say, moving a Linux script to a BSD or AIX box. I remember something I'd done which used, IIRC, $UID, without realizing it was a bashism, instead of using id -u.
I'll also note that all *production* scripts were once required to be bourne, but by the mid-ninties, management was starting to mandate that they be Korn shell, instead, for many reasons - capabilities, etc. Bash - I don't think I saw that till I started running RH 5.1, I think it was, about 18 years ago....
mark