use alternatives for man, apropos and whatis

man-db.spec

@@ -4,7 +4,7 @@
 Summary: Tools for searching and reading man pages
 Name: man-db
 Version: 2.9.1
-Release: 1%{?dist}
+Release: 2%{?dist}
 # GPLv2+ .. man-db
 # GPLv3+ .. gnulib
 License: GPLv2+ and GPLv3+
@@ -36,6 +36,10 @@ BuildRequires: systemd
 BuildRequires: gdbm-devel, gettext, groff, less, libpipeline-devel, zlib-devel
 BuildRequires: po4a, perl-interpreter, perl-version
 
+Requires(post): %{_sbindir}/update-alternatives
+Requires(postun): %{_sbindir}/update-alternatives
+Requires(preun): %{_sbindir}/update-alternatives
+
 %description
 The man-db package includes five tools for browsing man-pages:
 man, whatis, apropos, manpath and lexgrog. man formats and displays
@@ -73,6 +77,14 @@ make check
 %install
 make install DESTDIR=$RPM_BUILD_ROOT prefix=%{_prefix} INSTALL='install -p'
 
+# rename files for alternative usage
+for f in man apropos whatis; do
+    mv %{buildroot}%{_bindir}/$f %{buildroot}%{_bindir}/$f.%{name}
+    touch %{buildroot}%{_bindir}/$f
+    mv %{buildroot}%{_mandir}/man1/$f.1 %{buildroot}%{_mandir}/man1/$f.%{name}.1
+    touch %{buildroot}%{_mandir}/man1/$f.1
+done
+
 # move the documentation to the relevant place
 mv $RPM_BUILD_ROOT%{_datadir}/doc/man-db/* ./
 
@@ -103,31 +115,51 @@ install -D -p -m 0644 %{SOURCE4} $RPM_BUILD_ROOT%{_unitdir}/man-db-restart-cache
 %find_lang %{name}
 %find_lang %{name}-gnulib
 
-# stop and disable timer from previous builds
 %pre
+# stop and disable timer from previous builds
 if [ -e /usr/lib/systemd/system/mandb.timer ]; then
-  if test -d /run/systemd; then
+    if test -d /run/systemd; then
-	systemctl stop man-db.timer
+        systemctl stop man-db.timer >/dev/null 2>&1 || :
-	systemctl -q disable man-db.timer
+        systemctl -q disable man-db.timer >/dev/null 2>&1 || :
-  fi
+    fi
 fi
 
+%post
+# set up the alternatives files
+%{_sbindir}/update-alternatives --install %{_bindir}/man man %{_bindir}/man.%{name} 300 \
+    --slave %{_bindir}/apropos apropos %{_bindir}/apropos.%{name} \
+    --slave %{_bindir}/whatis whatis %{_bindir}/whatis.%{name} \
+    --slave %{_mandir}/man1/man.1.gz man.1.gz %{_mandir}/man1/man.%{name}.1.gz \
+    --slave %{_mandir}/man1/apropos.1.gz apropos.1.gz %{_mandir}/man1/apropos.%{name}.1.gz \
+    --slave %{_mandir}/man1/whatis.1.gz whatis.1.gz %{_mandir}/man1/whatis.%{name}.1.gz \
+    >/dev/null 2>&1 || :
+
 # clear the old cache
-%post
+%{__rm} -rf %{cache}/* >/dev/null 2>&1 || :
-%{__rm} -rf %{cache}/*
+
+%preun
+if [ $1 -eq 0 ]; then
+    %{_sbindir}/update-alternatives --remove man %{_bindir}/man.%{name} >/dev/null 2>&1 || :
+fi
+
+%postun
+if [ $1 -ge 1 ]; then
+    if [ "$(+readlink %{_sysconfdir}/alternatives/man+)" == "%{_bindir}/man.%{name}" ]; then
+        %{_sbindir}/update-alternatives --set man %{_bindir}/man.%{name} >/dev/null 2>&1 || :
+    fi
+fi
 
-# update cache
 %transfiletriggerin -- %{_mandir}
-if [ -x /usr/bin/systemd-run -a -x /usr/bin/systemctl ]; then
-    /usr/bin/systemd-run /usr/bin/systemctl start man-db-cache-update >/dev/null 2>&1 || :
-fi
-
 # update cache
-%transfiletriggerpostun -- %{_mandir}
 if [ -x /usr/bin/systemd-run -a -x /usr/bin/systemctl ]; then
     /usr/bin/systemd-run /usr/bin/systemctl start man-db-cache-update >/dev/null 2>&1 || :
 fi
 
+%transfiletriggerpostun -- %{_mandir}
+# update cache
+if [ -x /usr/bin/systemd-run -a -x /usr/bin/systemctl ]; then
+    /usr/bin/systemd-run /usr/bin/systemctl start man-db-cache-update >/dev/null 2>&1 || :
+fi
 
 %files -f %{name}.lang -f %{name}-gnulib.lang
 %{!?_licensedir:%global license %%doc}
@@ -139,10 +171,13 @@ fi
 %{_unitdir}/man-db-cache-update.service
 %{_unitdir}/man-db-restart-cache-update.service
 %{_sbindir}/accessdb
-%{_bindir}/man
+%ghost %{_bindir}/man
+%ghost %{_bindir}/apropos
+%ghost %{_bindir}/whatis
+%{_bindir}/man.%{name}
+%{_bindir}/apropos.%{name}
+%{_bindir}/whatis.%{name}
 %{_bindir}/man-recode
-%{_bindir}/whatis
-%{_bindir}/apropos
 %{_bindir}/manpath
 %{_bindir}/lexgrog
 %{_bindir}/catman
@@ -155,13 +190,16 @@ fi
 %{_libexecdir}/man-db/zsoelim
 %verify(not mtime) %dir %{cache}
 # documentation and translation
-%{_mandir}/man1/apropos.1*
+%ghost %{_mandir}/man1/man.1*
-%{_mandir}/man1/lexgrog.1*
+%ghost %{_mandir}/man1/apropos.1*
-%{_mandir}/man1/man.1*
+%ghost %{_mandir}/man1/whatis.1*
+%{_mandir}/man1/man.%{name}.1*
+%{_mandir}/man1/apropos.%{name}.1*
+%{_mandir}/man1/whatis.%{name}.1*
 %{_mandir}/man1/man-recode.1*
+%{_mandir}/man1/lexgrog.1*
 %{_mandir}/man1/manconv.1*
 %{_mandir}/man1/manpath.1*
-%{_mandir}/man1/whatis.1*
 %{_mandir}/man5/manpath.5*
 %{_mandir}/man8/accessdb.8*
 %{_mandir}/man8/catman.8*
@@ -187,6 +225,9 @@ fi
 %config(noreplace) %{_sysconfdir}/cron.daily/man-db.cron
 
 %changelog
+* Wed Feb 26 2020 Nikola Forró <nforro@redhat.com> - 2.9.1-2
+- use alternatives for man, apropos and whatis
+
 * Wed Feb 26 2020 Nikola Forró <nforro@redhat.com> - 2.9.1-1
 - update to 2.9.1
   resolves #1807144