Knowledge Base:Unmasking a package

Not all software present in the Gentoo repository will be immediately available to install with the emerge command. Software that is broken, for one reason or another, is masked and needs to be explicitly unmasked if it really must be installed.

Trying to emerge a masked package
On trying to install a masked package from the Gentoo repository, emerge will quit after issuing a warning that will look something like this :

Unmasking a package
Unmasking a package will enable installation of packages that have been marked against use.

Unmask automatically with emerge --autounmask-write
Re-running the command with   automatically queues the required text file alteration:

As with all configuration files, the final update is made by running (or alternatively ):

Examine the output of the configuration files, press  to exit the pager (if no commands appear at the end), and then  for use-new to accept the alterations. Press to zap (disregard) the changes.

Finally, re-run one last time:

Flat file
Create the directory if it does not yet exist:

Add the required line to a (new) file:

Using directories
Create the directory if it does not yet exist:

Create a file (or files) for the unmask operations to perform. For instance, to unmask the  package as mentioned earlier, run:

Most masked packages will not accept generic keywords, so specific keywords may need to be granted for the masked package.

How packages are masked
Developers explicitly mask out a package by mentioning it in the file in each profile. The masked file can be coupled with an explanation as to why the package has been masked.

Packages can also be masked by system administrators using.

See Knowledge Base:Masking a package for more information.