Good catch. It is nice we have fuction prototypes for CAL.

And what also is good with N900 is that it looks like libcal now does the dirty work of actually reading/writing config partition. So this makes it possible (not sure how legal) to write safely to config partition from other non-Maemo systems by either statically linking to libcal or copying libcal to target system.

This was not the case with N8x0 and below. For N8x0/770 all the dirty work was done by dsme so if dsme was not running there was no way to read/write CAL except reverse-engineering the format of config partition. That's why I could not easily read root device in bootmenu (via cal-tool -r) early enough to not to display "press menu key for advanced bootmenu .." when the stored root device starts with "ask" (=>the message is not needed). It did not work until dsme was started and then is was too late for the message.

So there was libcal too but all it did on previous devices is sending data to /tmp/dsmesock and letting dsme do it. It was even possible to somehow safely write anything to CAL area too (just strace cal-tool -R ask:mmc and see what it sents to dsme) but it was not so much useful for free Maemo replacement solutions since initfs and dsme is still needed.

Still, if it is useful for Mer etc. on 770/N8x0 it could be done. Or at least I hope so. I started code for writing r&d mode for previous tablets months ago but never finished it (lack of time, low priority). I hope dsme does not do any checking on possible CAL variable name when writing. It is quite likely since in OS2008 there is osso-product-info which writes 'random' values to CAL area too (via /usr/lib/libcal.so.*->dsme->/mnt/initfs/usr/lib/dsme/libcalmodule.so.*)