The Sigar API provides a portable interface for gathering system information such as: System memory, swap, cpu, load average, uptime, logins Per-process memory, cpu, credential info, state, arguments, environment, open files File system detection and metrics Network interface detection, configuration info and metrics TCP and UDP connection tables Network route table This information is available in most operating systems, but each OS has their own way(s) providing it. SIGAR provides developers with one API to access this information regardless of the underlying platform. The core API is implemented in pure C with bindings currently implemented for Java, Perl, Ruby, Python, Erlang, PHP and C#.
Created attachment 291261 [details] sigar-1.6.5.ebuild
external functions need die
The ebuild requires some patch you didn't attach.
Packaged as dev-ruby/sigar.