sh man page ....

[Valeri Galtsev]

On Fri, October 10, 2014 10:30 am, Michael Sierchio wrote:
> On Fri, Oct 10, 2014 at 8:30 AM, William A. Mahaffey III <wam at hiwaay.net>
> wrote:
>
>>.....I had a bunch of shell scripts written to use Linux
>> sh, which was in fact bash, which means it had a superset of the
>> arithmetic
>> operators that traditional sh had. When I use these scripts under sh
>> under
>> FBSD 9.3, they largely work, though there are some minor differences
>> (empty
>> strings evaluate to zero (0) under bash, error under sh). The man page
>> for
>> sh doesn't reflect some of these compatibilities/incompatibilities,
>
> Nor should it. The Bourne Shell is the Bourne Shell, is adequately
> documented by the man page, and warnings about incompatibility are the
> responsibility of those who foist off bash as sh.
>
> You're blaming your own bad habit on others. :-)
>

Let me second it.

I recently re-discovered (yes, I knew it since long ago, just forgot) that
Linuxes usually have "sh" as a symlink just pointing to bash. It kind of
kicked me out of my chair: security wise (and in general) you shouldn't
use large code (which bash is) to do just a small set of "features" (which
sh is). It just reminded me that Linux started in general as a "hack" and
still didn't fully grew out of it...

Valeri

++++++++++++++++++++++++++++++++++++++++
Valeri Galtsev
Sr System Administrator
Department of Astronomy and Astrophysics
Kavli Institute for Cosmological Physics
University of Chicago
Phone: 773-702-4247
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