[Fedora-packaging] Questions about dependencies in rpm packages

[Olivier Bourdon]

Hello

I have been using this wonderfull Fedora distro since FC2 and I am
currently using FC8 migrating soon to
FC10 as soon as it becomes official at the end of the month

One thing just started puzzling me is when I look at the list of
dependencies of say BackupPC

rpm -qp --requires BackupPC-3.0.0-3.fc8.noarch.rpm  | sort | uniq -c |
sort -n | tail
      1 rsync
      1 /usr/bin/perl
      1 /usr/sbin/useradd
      1 /usr/sbin/usermod
      2 chkconfig
      2 perl(Archive::Zip)
      2 perl(Compress::Zlib)
      2 perl(XML::RSS)
      3 initscripts
      5 /bin/sh

why are some of these duplicated ?

I can guess from the src.rpm file for initscripts that this comes from
the lines:
Requires(preun): initscripts, chkconfig
Requires(post): initscripts, chkconfig, %{_sbindir}/usermod
Requires(postun): initscripts

but what about /bin/sh ??

Furthermore using a specific formating string like
rpm -q -p --qf '[%{REQUIRENAME} %|REQUIREFLAGS?{%{REQUIREFLAGS:depflags}
%{REQUIREVERSION}}:{}|\n]' BackupPC-3.0.0-3.fc8.noarch.rpm

what should be the format string to potentially get the "differences"
between all expressed dependencies
Tried several choices but without much success

Thanks for your time & help