[U-Boot-Users] RFC: hidden environment variables

Timur Tabi timur at freescale.com
Mon Apr 23 18:46:58 CEST 2007

WD et al:

I'd like to propose a new feature for U-Boot: hidden environment variables.  These are 
variables that are stored in environment but are normally not visible to the user. 
Specifically, a hidden environment variable would have these properties:

1) Doesn't show up via "print" or "echo"
2) Can't be referenced via a $
3) Can't be set via setenv

Only internal U-Boot code can modify/query these variables.  This way, internal code can 
use the existing environment data structure without having to expose this data to the user 
(and giving him the impression that he can access/manipulate this data directly).

The only drawback to this plan is that, after modifying a hidden environment variable, the 
user would need to be told to issue "saveenv" if he wants his changes saved permanently.

One advantage of this feature is that we can develop new commands that store data 
permanently without having to add hooks into _do_setenv().

Timur Tabi
Linux Kernel Developer @ Freescale

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