Package management system few tips / trick to build / modify / work with packages.
Many hints information taken from original site RPM

rpm --scripts -qp <rpmfile>

Name of Package : libtorrent
Building it in folder “/usr/local/src/libtorrent”

mkdir /usr/local/src/libtorrent
cd /usr/local/src/libtorrent
mkdir BUILD RPMS SOURCES SPECS SRPMS

Creating macro not bad idea.

| /usr/local/src/libtorrent/.rpmmacros

%packager Ketan Patel

Get Sources from libtorrent
Place it in “/usr/local/src/libtorrent/SOURCES”
I have used following method.

cd /usr/local/src/libtorrent/SOURCES
svn co svn://rakshasa.no/libtorrent/trunk/libtorrent libtorrent
tar -cvf /usr/local/src/libtorrent/SOURCES/libtorrent.tar.gz libtorrent

Considering building rtorrent at non standard location.

NOTE : Please make sure code below has some SUSE Based Customization

| /usr/local/src/libtorrent/SPECS/libtorrent.spec

%define name libtorrent
%define srcdir /usr/local/src
%define _topdir %{srcdir}/libtorrent
 
 
summary: rTorrent
name: libtorrent
Source: libtorrent.tar.gz
License: GPL
version: 1
release: 1
Group: System/Utils
Prefix: /opt/libtorrent
buildarch: x86_64
BuildRoot: %{prefix}/%{name}-%{version}-%{release}-%{buildarch}-root
%define lib %{prefix}/lib64
%define include %{prefix}/include
Provides: libtorrent
Requires: ncurses, libcppunit-devel
AutoReqProv: no
 
 
%description
libtorrent is a BitTorrent client for ncurses, using
the libtorrent library. The client and library is
written in C++ with emphasis on speed and efficiency, while delivering
equivalent features to those found in GUI based clients in an ncurses
client.
 
%prep
%setup -q -n libtorrent
 
 
%build
chmod 755 autogen.sh
./autogen.sh
%{suse_update_config -f}
autoreconf -fiv
./configure --prefix=%{prefix} --libdir=%{lib}
make prefix=$RPM_BUILD_ROOT
 
%install
rm -rf %{buildroot}
make DESTDIR=$RPM_BUILD_ROOT install
rm -rf $RPM_BUILD_ROOT/%{prefix}/usr
 
 
%clean
make clean
rm -rf %{buildroot}
 
%files
%defattr(-,root,root,-)
%doc README
/opt/libtorrent/lib64/*
/opt/libtorrent/include/*
 
%post
echo "/opt/libtorrent/lib64/" > /etc/ld.so.conf.d/libtorrent.conf
ldconfig
 
%postun
rm -rf %{prefix}
rm /etc/ld.so.conf.d/libtorrent.conf
ldconfig
 
%Changelog
* Mon Nov 08 2010 Seriously, Check release son!!
Initial Build

cd /usr/local/src/libtorrent

rpmbuild -v -bb --clean SPECS/libtorrent.spec

OR

rpmbuild -ba SPECS/libtorrent.spec

rpm -Vp RPMS/x86_64/libtorrent-1-1.x86_64.rpm

| sample.spec

Name:      xgauguin-support
Summary:   xGauguin support metapackage
Version:   20110513
Release:   1.blip
Vendor:    lithiumfox
License:   none
Group:     Applications
URL:       http://lithiumfox.com
BuildRoot: %{_tmppath}/%{name}-%{version}-%(id -u -n)
BuildArch: noarch
Requires:  nginx, perl(Image::Size), perl(Params::Validate), perl(DateTime::Locale), perl(Class::Load), perl(parent), perl(DateTime::TimeZone), perl(Class::Singleton), perl(Test::Exception), perl(DateTime), perl(Image::Magick), perl(GD), perl(LWP), ImageMagick, gd, yum-utils
 
%description
Gauguin supporting packages
 
%install
[ "%{buildroot}" != "/" ] && %{__rm} -rf %{buildroot}
%{__mkdir_p} %{buildroot}%{_localstatedir}/www/releases
%{__mkdir_p} %{buildroot}%{_localstatedir}/tmp/cache
 
%pretrans
## Force installation of conflicts
# libxml2.i386, perl-Locale-Codes
if $( ! rpm -q libxml2.i386 > /dev/null 2>&1)
  then
 
    yumdownloader libxml2.i386 > /dev/null 2>&1
    %{__rm} /var/lib/rpm/__db.000 > /dev/null 2>&1
    rpm --force -ivh libxml2*.rpm 
    %{__rm} libxml2*.rpm > /dev/null 2>&1
fi
 
if $( ! rpm -q perl-Locale-Codes > /dev/null 2>&1)
  then
    set -m
    yumdownloader perl-Locale-Codes > /dev/null 2>&1
    %{__rm} /var/lib/rpm/__db.000 > /dev/null 2>&1
    rpm --force -ivh perl-Locale-Codes*.rpm > /dev/null 2>&1
    %{__rm} libxml2*.rpm > /dev/null 2>&1
fi
 
%pre
## Check if vlad user exists, if not add them
if $( ! id vlad >/dev/null 2>&1) 
   then
     groupadd -g 1029 vlad > /dev/null 2>&1 ||: 
     useradd -u 1029 -g 1029 -d /home/vlad -s /bin/bash -p '$1asdf0' -m vlad > /dev/null 2>&1
fi
 
##Add user to sudoers
if $( ! grep vlad /etc/sudoers >/dev/null 2>&1)
  then
    echo "vlad ALL=NOPASSWD: /etc/init.d/nginx" >> /etc/sudoers
fi
 
%post
##Add nginx to startup
chkconfig --level 345 nginx on
 
##Create symlink for nginx.conf
if [ ! -h /etc/nginx/nginx.conf ]
  then
   ln -f -s %{_localstatedir}/www/prod/gauguin/current/conf/nginx-prod.conf %{_sysconfdir}/nginx/nginx.conf
fi 
 
 
%files
%defattr(-,root,root)
%attr(-,vlad,-) %{_localstatedir}/www/prod/xgauguin
%attr(777,-,-) %{_localstatedir}/tmp/xgauguin-cache
 
%changelog
* Fri May 13 2010 Jason Thomas <jason@lithiumfox.com> - %{version}
- Initial package creation

You can use following one liner for changelog.

awk '{print "*", $1, $2, $3, $6, "Jason Thomas <jason@lithiumfox.com>","-", "%{version}""\n""- initial rpm creation"}' <(date)

Fedora Package
OpenSUSE Build Service
RPM Official

rpm -qpl file.rpm

Mock is a really nice tool to generate RPM cleanly.
I used KVM / MOCK to build RPM for my own reasons but you can use just mock and clean env. after every build.

General Details Available at Mock Project Page

Rather then guessing i have pasted all the command i have used to build RPM from srpm.
Using / Generating Spec require another tutorial this is strictly about some work around and keeping env. between transaction.

yum install mock

I am using rpmbuild user.

usermod -a -G mock rpmbuild

Before you work on anything Please initialize the environment.
It is good practice to initialize Environment between every build cycle to clean any possible left over or unforeseen issue.

mock --init -r epel-5-x86_64

You can not run mock as root so ….

su rpmbuild

I found that installed package stays installed during cycles.
So you do not require to install packages every time unless you initialize env.

/usr/bin/mock --install -r epel-5-x86_64 perl-libwww-perl.noarch

<note important>Dont scratch over –copyin check spelling one more time</note>

/usr/bin/mock -r epel-5-x86_64 --copyin pgpool-II-3.1.2.tar.gz /tmp/

cd ~
wget http://ftp.arix.com/cpan2rpm-2.028-1.src.rpm

<note> –no-clean : this will keep your files intact in build env.
–no-cleanup-after : i wanted to keep all work file so i used this just incase. </note>

/usr/bin/mock --rebuild --no-clean --no-cleanup-after -r epel-5-x86_64 cpan2rpm-2.028-1.src.rpm

In general case result will be stored in '/var/lib/mock/epel-5-x86_64/result/'