Process::Sys (UID/GID) for mruby
- add conf.gem line to 
build_config.rb 
MRuby::Build.new do |conf|
    # ... (snip) ...
    conf.gem :github => 'haconiwa/mruby-process-sys'
endp Process::Sys.getuid
#=> 1000
p Process::Sys.getgid
#=> 1000
include Process
UID.eid
#=> 1000
UID.from_name "haconiwa"
#=> 1001
#...See Ruby reference manual: Process::Sys Process::UID Process::GID
and test directory.
MIT