sincere thanks
Gottfried

a good explanation is always useful, also for others who will look in 
the history.


Am 24.10.22 um 14:40 schrieb Tobias Geerinckx-Rice:
> Hi Gottfried,
> 
> I hope this strikes the right balance between explaining ‘environment 
> variables’ from scratch and answering your immediate question.
> 
> Gottfried 写道：
>> 1.  Will this now overwrite my variables for ever, or only for some time?
> 
> Environment variables are not saved.  They can be *set* by configuration 
> files, such at /etc/profile, but these files are not updated when you 
> type ‘export GUIX=awesome’ on the command line.
> 
> Setting LC_ALL like this affects your current shell, and it will be 
> inherited by child processes (hence why the ‘guix’ child will speak 
> English after setting LC_ALL=C in the parent shell), but they exist 
> purely in RAM for the lifetime of each process.
> 
> The also do not propagate to ancestor or sibling processes: setting 
> LC_ALL in one terminal window has no effect on any other windows.  Nor 
> will setting LC_ALL in a shell affect new processes you launch 
> elsewhere, such as from your desktop menu.  Only child processes 
> launched in the same shell/window will inherit it.
> 
> As soon as you close that terminal, type ‘exit’ in the (guix) shell, or 
> trip over your power cable, the setting is gone.
> 
>> 2.  How can I set it back to my original state?
> 
> Environment variables have no built-in notion of history, or defaults.  
> They are just variables, and setting them to something new overwrites 
> the old value (if any).
> 
> So:
> 
> ~$ echo $LC_ALL        # yours will be de_DE, I presume
> en_IE.utf8
> ~$ LC_OLD=$LC_ALL    # save the old value
> ~$ export LC_ALL=C    # in with the new
> ~$ echo $LC_ALL        # do the thing
> C
> ~$ LC_ALL=$LC_OLD    # restore the old value
> 
> But really, in practice, I'd just close the window/shell once done…  
> they are so cheap.
> 
> Kind regards,
> 
> T G-R