[yocto] Extending images

[Gary Thomas]

I've always used 'IMAGE_INSTALL += " xyz"' in my local.conf
to add new packages to a build.  That said, I had a working
build for qemuarm (probably doesn't matter) and I added:
   IMAGE_INSTALL += " strace"
This produced a completely broken image which barely came
up to a shell, lots of missing programs, etc.

I then tried
   CORE_IMAGE_EXTRA_INSTALL += " strace"
which produced a perfectly working build (just as previous)
with the new package added.

I can see that the images produced are vastly different:

* Original working build
-rw-r--r-- 1 gthomas gthomas     11719 Jul 18 09:34 core-image-sato-qemuarm-20140718124453.rootfs.manifest
-rw-r--r-- 1 gthomas gthomas  87611203 Jul 18 09:34 core-image-sato-qemuarm-20140718124453.rootfs.tar.bz2

* After 'IMAGE_INSTALL += '
-rw-r--r-- 1 gthomas gthomas      9986 Jul 18 09:55 core-image-sato-qemuarm-20140718155134.rootfs.manifest
-rw-r--r-- 1 gthomas gthomas  37859884 Jul 18 09:56 core-image-sato-qemuarm-20140718155134.rootfs.tar.bz2

* After 'CORE_IMAGE_EXTRA_INSTALL += '
-rw-r--r-- 1 gthomas gthomas     11738 Jul 18 10:05 core-image-sato-qemuarm-20140718160108.rootfs.manifest
-rw-r--r-- 1 gthomas gthomas  87720106 Jul 18 10:05 core-image-sato-qemuarm-20140718160108.rootfs.tar.bz2

What's the difference and why did the first attempt fail?

Thanks

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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