Here is a small reminder on how to install xdtv from an ebuild
that is not yet in portage:

- check in /etc/make.conf that PORTDIR_OVERLAY is defined. In the
following, we assume its location is /usr/local/portage

- create a directory for xdtv in the overlay:
# mkdir -p /usr/local/portage/media-tv/xdtv
# cd /usr/local/portage/media-tv/xdtv

- copy there the ebuild, for instance from the sources tree:
# cp /tmp/xdtv-X.Y.Z/gentoo/xdtv.ebuild xdtv-X.Y.Z.ebuild

- if you already have the tarball file, put it in
/usr/portage/distfiles. Else, fetch it:
# GENTOO_MIRRORS="" ebuild xdtv-X.Y.Z.ebuild fetch

- create the digest:
# ebuild xdtv-X.Y.Z.ebuild digest

- check the available USE flags:
# ACCEPT_KEYWORDS="~x86" emerge -pv xdtv

- emerge xdtv:
# ACCEPT_KEYWORDS="~x86" emerge xdtv



Thanks to TGL to these infos.

PS: X.Y.Z = current xdtv version (for example 2.0.0).