diff --git a/rrdtool.changes b/rrdtool.changes
index 6ff33ba..809c6ae 100644
--- a/rrdtool.changes
+++ b/rrdtool.changes
@@ -1,3 +1,11 @@
+-------------------------------------------------------------------
+Tue Dec  6 12:59:16 UTC 2016 - jengelh@inai.de
+
+- Implement shared library packaging guideline
+- Reduce %serivce_* calls, speed up find by using {}+ instead,
+  rectify RPM groups, trim descriptions.
+- Abort package installation when user/group cannot be created.
+
 -------------------------------------------------------------------
 Thu Dec  1 16:44:25 UTC 2016 - luizluca@tre-sc.jus.br
 
diff --git a/rrdtool.spec b/rrdtool.spec
index a899e2d..9de3b1a 100644
--- a/rrdtool.spec
+++ b/rrdtool.spec
@@ -71,28 +71,37 @@ BuildRequires:  librados2-devel
 Requires:       dejavu
 
 %description
-RRD is the Acronym for Round Robin Database. RRD is a system to store and
+RRD stands for Round Robin Database. RRD is a system to store and
 display time-series data (i.e. network bandwidth, machine-room temperature,
-server load average). It stores the data in a very compact way that will not
+server load average). It stores the data in a compact way that will not
 expand over time, and it presents useful graphs by processing the data to
 enforce a certain data density. It can be used either via simple wrapper
 scripts (from shell or Perl) or via frontends that poll network devices and
 put a friendly user interface on it.
 
 
+%package -n librrd8
+Summary:        Round Robin Database tool library
+Group:          System/Libraries
+
+%description -n librrd8
+RRD stands for Round Robin Database. RRD is a system to store and
+display time-series data.
+
 %package devel
-Summary:        RRDtool libraries and header files
+Summary:        RRDtool header files
 Group:          Development/Libraries/C and C++
-Requires:       %{name} = %{version}-%{release}
+Requires:       librrd8 = %{version}-%{release}
 
 %description devel
-RRD is the Acronym for Round Robin Database. RRD is a system to store and
+RRD stands for Round Robin Database. RRD is a system to store and
 display time-series data (i.e. network bandwidth, machine-room temperature,
-server load average). This package allow you to use directly this library.
+server load average). This package allow you to build programs making
+use of the library.
 
 
 %package doc
-Summary:        RRDtool documentation
+Summary:        Documentation for rrdtool
 Group:          Documentation
 
 %description doc
@@ -181,7 +190,8 @@ Summary:        Data caching daemon for RRDtool
 Group:          Productivity/Scientific/Math
 Requires:       %{name} = %{version}-%{release}
 Requires(pre):  %fillup_prereq
-Requires(pre):  pwdutils
+Requires(pre):  /usr/sbin/useradd
+Requires(pre):  /usr/sbin/groupadd
 
 %description cached
 rrdcached is a daemon that receives updates to existing RRD files,
@@ -200,7 +210,7 @@ daemon was written to alleviate these problems.
 modified="$(sed -n '/^----/n;s/ - .*$//;p;q' "%{_sourcedir}/%{name}.changes")"
 DATE="\"$(date -d "${modified}" "+%%b %%e %%Y")\""
 TIME="\"$(date -d "${modified}" "+%%R")\""
-find . -name '*.c' -exec sed -i "s/__DATE__/${DATE}/g;s/__TIME__/${TIME}/g" {} \;
+find . -name '*.c' -exec sed -i "s/__DATE__/${DATE}/g;s/__TIME__/${TIME}/g" "{}" "+"
 
 %build
 %configure \
@@ -274,7 +284,7 @@ find %{buildroot}%{_libdir} -type f -name "*.la" -delete -print
 
 # documentation
 rm %{buildroot}%{_docdir}/%{name}/txt/*.pod
-find %{buildroot}%{_docdir}/%{name}/examples/ -type f -exec chmod 0644 {} \;
+find %{buildroot}%{_docdir}/%{name}/examples/ -type f -exec chmod 0644 "{}" "+"
 
 # install rrdcached specials
 install -D -m 644 %{SOURCE2} %{buildroot}%{_localstatedir}/adm/fillup-templates/sysconfig.rrdcached
@@ -290,15 +300,13 @@ mkdir -p %{buildroot}%{_sbindir}
 ln -s %{_sbindir}/service %{buildroot}%{_sbindir}/rcrrdcached
 
 %pre cached
-getent group %{rrdcached_group} >/dev/null || groupadd %{rrdcached_group} || :
-getent passwd %{rrdcached_user} >/dev/null || useradd -s /sbin/nologin -g %{rrdcached_group} -c %{rrdcached_user} -d %{_localstatedir}/lib %{rrdcached_user} || :
-%service_add_pre rrdcached.service
-%service_add_pre rrdcached.socket
+getent group %{rrdcached_group} >/dev/null || groupadd %{rrdcached_group}
+getent passwd %{rrdcached_user} >/dev/null || useradd -s /sbin/nologin -g %{rrdcached_group} -c %{rrdcached_user} -d %{_localstatedir}/lib %{rrdcached_user}
+%service_add_pre rrdcached.service rrdcached.socket
 
 %post cached
 %fillup_only rrdcached
-%service_add_post rrdcached.service
-%service_add_post rrdcached.socket
+%service_add_post rrdcached.servicet rrdcached.socket
 %if 0%{?suse_version} <= 1320
 systemd-tmpfiles --create %{_tmpfilesdir}/rddcached.conf >/dev/null 2>&1 || :
 %else
@@ -306,16 +314,13 @@ systemd-tmpfiles --create %{_tmpfilesdir}/rddcached.conf >/dev/null 2>&1 || :
 %endif
 
 %preun cached
-%service_del_preun rrdcached.service
-%service_del_preun rrdcached.socket
+%service_del_preun rrdcached.service rrdcached.socket
 
 %postun cached
-%service_del_postun rrdcached.service
-%service_del_postun rrdcached.socket
+%service_del_postun rrdcached.service rrdcached.socket
 
-%post -p /sbin/ldconfig
-
-%postun -p /sbin/ldconfig
+%post   -n librrd8 -p /sbin/ldconfig
+%postun -n librrd8 -p /sbin/ldconfig
 
 %files
 %defattr(-,root,root,-)
@@ -325,6 +330,9 @@ systemd-tmpfiles --create %{_tmpfilesdir}/rddcached.conf >/dev/null 2>&1 || :
 %exclude %{_mandir}/man3/RRD*
 %{_bindir}/*
 %exclude %{_bindir}/rrdcached
+
+%files -n librrd8
+%defattr(-,root,root)
 %{_libdir}/librrd.so.*
 
 %files devel