making a list of the *fundamental* variables used by image.bbclass

for class purposes, i want to make a *short* list of the really
fundamental variables used to define the final content of an image as used by image.bbclass, and i want to know if there's anything i've missed from this list.

first, the obvious ones:

* IMAGE_FEATURES (image features, processed by image.bbclass)
* IMAGE_INSTALL (names of individual packages)

as i read it, those two variables pretty much define the final content of the image. i *don't* include things like EXTRA_IMAGE_FEATURES as that variable is already processed by bitbake.conf before image processing starts; that is, image.bbclass makes no reference to that variable, so it's not relevant here.

other variables that make a smaller difference but still processed
by image.bbclass:

* ROOTFS_PKGMANAGE
* SPLASH

there are also all those *_PROCESS_COMMAND variables (preprocess,
postprocess), but i haven't checked yet which of those are simply processed within image.bbclass based on the contents of IMAGE_FEATURES, or possibly something else.

ah, here's another one:

* DISTRO_FEATURES

which is tested for processing of systemd/sysvinit. (for similar reasons, MACHINE_FEATURES is not listed here as all of its processing is done outside the file.)

i'm still perusing the file but are there any variables i've
overlooked that are treated as *input* to image.bbclass that control the final image content? (i'm also ignoring things like fstype-related variables, not interested in the *format* of the final image, just the content.)

so what have i missed?

rday

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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