Friday, May 14, 2010

Fedora RPM Packaging In A Nutshell

I have talked about RPM and DEB in some of my older posts. Actually RPM and and DEB are installable packages analogous to .exe files for windows. In this post I won't teach you how to build an rpm but I will give you a vague idea and point out some resources and tutorial to get you started. Let us do it in a question-answer way.

Q. What do I need to build a rpm package?
A. The most important thing you need is the source code of the application. You will also need the packages required to build the application from the source a.k.a. the dependencies.

Q. Why should I build an rpm?
A. Not everyone is a techie like you. People have the habit of double clicking the stuff. rpm is for those people and it saves the effort of installing everything from scratch and remembering dependencies.

Q. How hard is it?
A. The general packaging procedure is not very hard but still sometimes packaging can take quite sometime. More dependencies increase difficulty of the package.

Q. From where should I start?
A. You can start by checking out the tutorial at A more advanced tutorial can be found at but if you are looking for a summary then this post will suffice.

Q. So, tell me how do I build rpm for an application?
A. That depends somewhat on the distro because every distro has different packaging guidelines. I will talk about Fedora here.
To create a package, you need to have a spec file first. Spec file consist of details about the package such as its name, version, dependencies, the way it is going to install etc. You can check out some spec files created by me here. Once you have created a spec file properly, you can easily create a package by rpmbuild command.

Q. How do I set up a nice packaging environment on my distro?
A. Again that is distro dependent. Being a hard core Fedora fan I will tell you how do setup the packaging environment on Fedora. Just fire the following commands:
yum install @development-tools
yum install rpm-build rpmdevtools

Q. I have the setup the packaging environment, what next?
A. Once you have created a packaging environment, you'll get a directory named rpmbuild in your home folder. Inside this folder you'll see several other folders. You need to put the archived source code along with relevant patches in SOURCE folder. After that you need to fire the following commands assuming that you are currently in SOURCES folder:
cd ../SPECS

This will create a spec file for the corresponding app. Now you need to fill the spec file with correct details. For this check out

Q. I have written a spec file. How do I get src.rpm and rpm from it?
A. Once you are sure about your spec file then you can get rpms using a very simple command:
rpmbuild -ba

You can find the rpm and src.rpm in relevant folders inside rpmbuild directory.

Well, there you go! You have the rpms ready to be used. Have fun!