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[Jørn Åne <jorn.dejong AT uninett.no>]

Den 20.01.2016 11.25, skrev Stefan Winter:
> Hi,
>
> > #!/bin/bash
>
> which is, as Wikipedia just told me, a "shebang":
>
> https://en.wikipedia.org/wiki/Shebang_%28Unix%29
>
> The article contains a portability section, and suggests to use:
>
> #!/usr/bin/env bash
>
> instead for higher chances of portability. Maybe this is worth a try? It
> does work on my machine; but the raw /bin/bash also does here.

Hi Stefan

Management summary: This seems like a good idea, I support this.

For Linux operating systems, I think it doesn't really matter. Every 
Linux I know about supports both /bin/bash and /usr/bin/env bash.

It gets more interesting when the CAT installer must support other 
UNIXes as well, such as {Free,Net,Open}BSD.  These operating systems 
come without bash built in, and if bash is installed using a package 
manager, it will generally not be located in /bin/bash, but rather 
somewhere like /usr/local/bin/bash or /usr/pkg/bin/bash.

This is the reason that using /usr/bin/env bash is more portable than 
/bin/bash. But keep in mind that even though using env is more portable,
the user still must have bash installed for the script to be able to run.

Example of a system without bash installed:
# /usr/bin/env bash
env: can't execute 'bash': No such file or directory
# /bin/bash
-sh: /bin/bash: not found

--
Jørn de Jong
Systemutvikler
UNINETT AS