Here is the whole bbclass:
DESCRIPTION = "Creates symlink to the latest version workdir of the package"
do_latest_link() {
if [ -n "${WORKDIR}" ]; then
linkname="$(dirname ${WORKDIR})/latest"
rm -f $linkname
ln -s $(basename ${WORKDIR}) $linkname
fi
}
addtask latest_link after do_unpack
do_unpack[postfuncs] += "do_latest_link"
But for better understanding I made the more throughout look into the documentations. I found the information about "postfuncs" you talk about [1]. However, the tasks description [2] doesn't say anything about including the task in the process, it just describes the demanded order that the task is put ( addtask something after|before othertask ).
That is so, until I read "3.6. Variable Flags" [3]. Where is quite clearly stated those variables control functionality and *dependencies*.
The documentation is quite unclear in that case.