Knowledge Base:Unmasking a package

Synopsis
Some software packages are masked out for usage. Any attempt to install such a package results in the warning from Portage that additional changes are needed before it can proceed:

Environment
Any Gentoo installation

Analysis
Next to the KEYWORDS settings in the ebuild, additional masking is available within Gentoo. Developers can explicitly mask out a package by mentioning it in the  file within the profiles together with an explanation why the package is masked out. Common reasons are prerelease versions of a certain software package, no more upstream development, known security issues in the package, etc.

Resolution
If you still need to unmask the package, create a directory  and inside it, create a file (or files) for the unmask operations you want to perform. For instance, to unmask the  package as mentioned earlier:

Most masked packages are also not accepting generic keywords, so you might need to accept keywords for the packages too.

Further Resources

 * Accepting a keyword for a single package on the Gentoo Wiki Knowledgebase