+ROOT
+
+
+
+The idea behind ROOT is that one can build a system with
+ROOT=/somewhere and then chroot into it or tar up /somewhere
+as a system image. It is not designed to allow the user to run
+/somewhere/usr/bin/foo.
+
+
+
+An ebuild could use ROOT in pkg_postinst() to conditionally print
+an error message if an old and obsolete configuration file still exists.
+
+
+pkg_postinst() {
+ if [ -e "${ROOT}/etc/oldconfig" ]; then
+ ewarn "You still have the obsolete config file "
+ ewarn " ${ROOT}/etc/oldconfig."
+ ewarn "Please migrate your settings to ${ROOT}/etc/newconfig"
+ ewarn "and remove ${ROOT}/etc/oldconfig."
+ fi
+}
+
+
+
+
+ROOT can't be used correctly in src_*, since ROOT might be
+different when merging a binary package. For example, a binary package might be
+built with ROOT=/ and then installed onto a system using
+ROOT=/somewhere.
+
+
+
+ROOT isn't used for library dependencies. When building, libraries,
+headers etc. on / have to be used.
+
+
+
+
+
+