Follow this procedure in order to install the ROHC library on a Gentoo Linux system. For other systems, see the generic installation procedure.

the gentoo ebuild is not up-to-date

a shelr screencast would be great

upload the ebuild on sunrise

The ROHC Ebuild is not in the Gentoo official tree yet. You have to get it from the Gentoo bugtracker.

Download the 3 following files:

• rohc-X.Y.X.ebuild = the Ebuild for the ROHC library version X.Y.Z
• metadata.xml = the metadata for ebuild of ROHC library
• ChangeLog = the changelog for ebuild of ROHC library

If you do not have a local tree on your Gentoo system yet, alter you portage configuration as follow to tell portage that a local tree is now present in /usr/local/portage/:

# echo "PORTDIR_OVERLAY=/usr/local/portage" >> /etc/make.conf

Create the local tree and put the 3 ROHC Ebuild files in it:

# mkdir -p /usr/local/portage/net-libs/rohc
# cp -f $DOWNLOAD_DIR/rohc-X.Y.X.ebuild /usr/local/portage/net-libs/rohc/
# cp -f $DOWNLOAD_DIR/metadata.xml /usr/local/portage/net-libs/rohc/
# cp -f $DOWNLOAD_DIR/ChangeLog /usr/local/portage/net-libs/rohc/

Create the manifest of the ROHC Ebuild:

# ebuild /usr/local/portage/net-libs/rohc/rohc-X.Y.X.ebuild manifest

The above command will download the source archive of the ROHC library and generate the related MD5/SHA checksums. The ROHC Ebuild is now available in your Gentoo system.

If you are running a stable Gentoo system, you have to keyword the ROHC Ebuild to be able to install it. If you are running a ~arch system, go directly to next step.

To keyword the ROHC Ebuild, type as root:

# echo "net-libs/rohc" > /etc/portage/package.keywords/rohc

If you get an error stating that /etc/portage/package.keywords/rohc is not a directory, it means that your system uses a single file for all keywords instead of a directory. Type the following command as root:

# echo "net-libs/rohc" >> /etc/portage/package.keywords

As root, tell portage to install the ROHC Ebuild:

# emerge -av net-libs/rohc

The following USE flags are available:

• debug = Off by default. Enable verbose output in the ROHC library. Do not use it except if you intend to debug or develop the library itself or an application using the library.
• doc = Off by default. Generate HTML documentation of the ROHC library API and performance graphs for the ROHC library. The app-doc/doxygen[latex,dot] and sci-visualization/gnuplot dependencies are then required. The documentation is installed in /usr/share/doc/rohc-X.Y.X/.
• rtp-bit-type = Off by default. Enable support for non-standard RTP bit type support.

The Ebuild supports testing if the “test” feature is enabled in your make.conf or if FEATURES=test is set in the commande line. Testing the ROHC library requires net-libs/libpcap to be installed.

Once the ROHC library is installed, you may:

• generate compression statistics for a recorded stream,
• test the ROHC library with your local network traffic,
• run the IP/ROHC tunnel application to establish a tunnel with compression capabilities between 2 machines,
• use the ROHC library in your own program.