Re: [PATCH] Add shell-quasiquote.

[David Kastrup]

"Stephen J. Turnbull" <address@hidden> writes:

> Eli Zaretskii writes:
>
>  > Next, I could see why users on a Posix host might want to execute
>  > some commands with a particular non-default shell.  I don't see why
>  > Emacs packages, perhaps with a sole exception of Tramp, would need
>  > that.
>
> Sometimes it pays to be precise.  All of the OS distributions gave up
> on bash because it didn't quite conform to POSIX (even when invoked in
> POSIX compatibility mode), and that caused bugs in package
> installation and management for packages that used sh scripts rather
> than perl or python.  That's why shells like ash and dash exist.

I think it was more a question of size and startup speed.  bash has a
lot of features beyond those in the POSIX specs, and the main arguments
I saw for replacing bash with dash on systems such as Ubuntu were based
on benchmarks.

This choice led to a lot of fun with people having to clean their shell
scripts from "bashisms", constructs not available in POSIX standards but
provided by bash.  The "function" keyword for shell functions is one of
the most frequent offenders.

-- 
David Kastrup