Frequently Asked Questions

Q: Why T2 when there is Gentoo?

A: Yeah, we actually get asked this one really often, ... T2, or more accurately it's precursor ROCK Linux, was already started in 1998 some month before Gentoo and also registered earlier on freshmeat - so, well, we started when there was no Gentoo and probably did not about the other project vice versa for quite some years. So both evolved unknown by each other in different ways.

Also on the technical side, T2 allows for more professional development, permanent target definitions, cross builds, alternative embedded C libraries and multiple init systems to choose from. Furthermore T2 packages usually do not contain any, or not much code and are based on a key-value text file making working and updating packages in T2 a snap. Patches are also versioned in-tree, and not distributed thru separate source mirrors.

Q: Why T2 when there are Embedded Gentoo, Embedded Debian and Open Embedded

A: We do not believe in a fork per use-case.

With T2 we do not need a so many dedicated forks. Instead the lightweight packaging system paired with the automated build process allows us to support all processor architectures, operating system kernel, C libraries and use-cases in just one single source tree.

OpenEmbedded is quite a young project focusing just on the embedded use-case as well. T2 on the other hand also targets servers and desktops beside the resource constrained embedded case.

Q: Why doesn't T2 use RPM packages?

A: First of all the RPM specs that are circulated by the commercial distributions are not cross compile aware. Furthermore the RPM format is a bit cryptic for our taste and does not match with our automated build process T2 was designed for. T2 uses it's own, lightweight key-value text meta-data format that was created exactly for this use-case.

Q: Why doesn't T2 use DEB packages?

A: First of all the DEB control files that are circulated by Debian, Ubuntu, are not cross compile aware and most of the points for RPM apply, likewise.

We also do not find the Debian-way of bundling all the changes in one big patch alongside the orig tarball very appealing. Instead in T2 you just drop a new patch in the package directory, no single "all-in-one" patch has to be updated and rediffed into the growing "debianization" .diff.gz. The single patches in T2 are supposed to be more developer, user, patch and version control friendly.

Q: Why do I need to be root to build T2?

A: Some packages need to install files with special ownership and permissions that are not allowed to set from a normal user account. Additionally non-cross build packages are build inside a chroot sandbox environment which requires root privilege as well. However we are working on this topic and expect future version to not require to be root to cross-build embedded targets.

Q: Outstanding work! How much $$$ does it cost?

A: Nothing, T2 is released for free under the terms of the GNU General Public License (GPL).

Q: GPL? Do I need to release my whole embedded system under the GPL as well?

A: No (of course not). T2 is a build system such as GNU make. It just builds the components together. Whether some components are binary-only with a proprietary license is up to you.

However, of course you have to honor the original licenses from the Linux kernel, over the glibc, uClibc and busybox et al. and republish those and your modifications, if any. If in doubt please consult your lawyer of choice for licensing and related questions.