[OE-core] what exactly is the proper way to use FILESEXTRAPATHS?

[Robert P. J. Day]

  continuing my trek through coding pedantry and was wondering about
the exact purpose of the common line in .bbappend files:

FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:"

or some slight variation thereof.

  i *thought* i knew what it did, so i did a small experiment with the
meta-ti layer and netbase (since i was already messing around with
it), and i replaced the contents of the netbase .bbappend file with
the single line:

FILESEXTRAPATHS_prepend := "rday"

and checked the environment for the value of FILESPATH for the netbase
recipe and, after formatting to read it clearly, what i saw was:

FILESPATH="rday/linux-gnueabi
rday/arm
rday/build-linux
rday/pn-netbase
rday/beagleboard
rday/omap3
rday/armv7a
rday/
rday/class-target
rday/forcevariable
rday/libc-glibc
rday/
/home/rpjday/OE/dist/layers/oe-core/meta/recipes-core/netbase/netbase-5.0/linux-gnueabi
/home/rpjday/OE/dist/layers/oe-core/meta/recipes-core/netbase/netbase-5.0/arm
/home/rpjday/OE/dist/layers/oe-core/meta/recipes-core/netbase/netbase-5.0/build-linux
/home/rpjday/OE/dist/layers/oe-core/meta/recipes-core/netbase/netbase-5.0/pn-netbase
/home/rpjday/OE/dist/layers/oe-core/meta/recipes-core/netbase/netbase-5.0/beagleboard
/home/rpjday/OE/dist/layers/oe-core/meta/recipes-core/netbase/netbase-5.0/omap3
... snip ...

  what the heck?  if that's what FILESEXTRAPATHS is supposed to do,
that is definitely *not* how it's being used in many, many bbappend
files.

  is there an explanation somewhere as to what the above is supposed
to represent?

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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