we have
$ grep sane /etc/services
sane            6566/tcp                        # SANE network server
igor@breeze src/repo/iscan.git $ rpm -qf /etc/services
setup-2.2.10-alt1
but found in iscan spec:
----------------------------------------------
# 	rpm (un)installation scripts

#  Believe it or not, but there are distros out there that do not have
#  the sane service listed in their /etc/services.  Also note that the
#  official service name, as registered with the IANA is not sane, but
#  sane-port.  The saned alias is also commonly used.
#
%pre
srv=/etc/services
if [ -z "`grep 6566/tcp ${srv}`" ]
then
    cat >> ${srv} <<EOF
sane-port       6566/tcp   sane saned   # SANE Control Port
sane-port       6566/udp   sane saned   # SANE Control Port
EOF
fi
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