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

Wolfgang Denk wd at denx.de
Mon Apr 23 23:46:15 CEST 2007

In message <1628E43D99629C46988BE46087A3FBB997ACAA at ep-01.EmbeddedPlanet.local> you wrote:
> You can implement an option that keeps a list of variables that should
> be hidden. That way, each variable can be checked against the list
> before printing it or allowing a user to change it from the prompt. With
> an implementation like this, everything continues to work if the
> hide_some_varibles option is not enabled. For example, variable
> 'hide_variable' could contain a list of other variables that are hidden.
> Of course, 'hide_variable' would have to be in its own list too. Then
> each variable can be searched for within 'hide_variable' before it is
> printed or changed. That does not sound that dificult and is completely
> backward compatable. 

... and will soon  become  terribly  slow.  Already  now  environment
variable  lookup  can  make  for a significant part of the total boot
time, especially on systems where the environment is  not  stored  in
flash memory (i. e. in EEPROM or data flash etc.).

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH, HRB 165235 Munich, CEO: Wolfgang Denk
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Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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ger than any hour. That's relativity.              -- Albert Einstein

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