From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfgang Denk Date: Mon, 13 Aug 2007 22:45:48 +0200 Subject: [U-Boot-Users] Using 'ver' env var In-Reply-To: Your message of "Mon, 13 Aug 2007 15:26:54 CDT." <5CBE65F7D9232C47861CB09B0954861C66A93C@MAIL.infinitychannel.local> Message-ID: <20070813204548.D6AF72405E@gemini.denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de In message <5CBE65F7D9232C47861CB09B0954861C66A93C@MAIL.infinitychannel.local> you wrote: > > > What makes you think so? saveenv does not do any filtering to exclude > > any variable, so of course it gets saved, too. > > It does, but only if you explicitly call 'saveenv'... It does not store > on it's own. Of course. U-Boot usually does only what you tell it. > > To print the U-Boot version without need to reset the board. > > But you can print it using 'version', too... And unless you explictly > save it, > the 'ver' env var does nothing more for you than the 'version' command, You can use the variable in commands, like for implementing version-dependent things, or test it, or ... > Can't be accessed anywhere other then from the u-boot command prompt... It is a normal environment variable like any other. It can be used whenever and whererver other variables can get used. This includes saving to flash and reading the flash from Linux. > If you don't explicitly 'saveenv' there is no 'ver' variable to read > from linux... > And it can't be good for the flash to force u-boot to save on every > boot. It's not needed to save this on every boot. It's perfectly sufficient to save it once after you've installed and booted a new version of U-Boot. > So if I update (from linux for example) 'ver' doesn't get updated unless > u-boot is > doing a saveenv on every boot... Not on every boot. It's sufficient to perform this on the first boot. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de 'What shall we do?' said Twoflower. 'Panic?' said Rincewind hope- fully. He always held that panic was the best means of survival; back in the olden days, his theory went, people faced with hungry sabre- toothed tigers could be divided very simply in those who panicked and those who stood there saying 'What a magnificent brute!' or 'Here, pussy.' - Terry Pratchett, _The Light Fantastic_