From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ulf Samuelsson Date: Mon, 23 Apr 2007 20:47:00 +0200 Subject: [U-Boot-Users] RFC: hidden environment variables References: <462CE302.7030302@freescale.com> Message-ID: <005f01c785da$03821550$9003960a@atmel.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de > 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 > I think an attribute byte for each variable would be nice. Then you can have attributes like: hidden user editable locked exectuable I would for instance like to treat ethaddr differently. This should be freely changeable until it is locked. I would also like to get rid of the "run" command and execute commands directly. These commands would be referencing commands which does not need to be visible. > 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 > Best Regards Ulf Samuelsson ulf at atmel.com Atmel Nordic AB Mail: Box 2033, 174 02 Sundbyberg, Sweden Visit: Kavalleriv?gen 24, 174 58 Sundbyberg, Sweden Phone +46 (8) 441 54 22 Fax +46 (8) 441 54 29 GSM +46 (706) 22 44 57 Technical support when I am not available: AT90 AVR Applications Group: mailto:avr at atmel.com AT91 ARM Applications Group: mailto:at91support at atmel.com AVR32 Applications Group mailto:avr32 at atmel.com http://www.avrfreaks.net/; http://avr32linux.org/ http://www.at91.com/ ; ftp://at91dist:distrib at 81.80.104.162/