Re: [PATCH] env: new option '-f/--file' to load variables from file

[Pádraig Brady]

On 16/01/2022 14:50, Pádraig Brady wrote:
> On 09/10/2021 12:38, Matthias de Clerk wrote:
> > Thanks! I hope some users will find this feature handy.
> >
> > Let me know if I can help.
>
> I still think the feature is useful.
>
> There are some issues in the implementation though,
> specifically in the syntax supported in the file
>
>    - It's not general, as no support for explicit $, \n
>    - It's not general, as can't append blah in $VARblah
>    - It diverges from the syntax supported in -S
>
> All this would be addressed by just reusing the escape
> and interpolation syntax supported by the -S option.
> I.e. only support curly brackets for interpolation,
> and support \$, \n etc.
> Note that also more generally/simply uses getenv()
> to do the lookup rather than reimplementing.

BTW, It would make sense for printenv(1) to take an option
to output in this escaped format.
That would allow printenv to prime a file for use by `env --file=...`,
and also better support subsequent line oriented processing.

cheers,
Pádraig