New FFI::IO.for_fd fails on Linux (and possibly other platforms) #390

headius@headius-Server:~/jruby$ jruby -Xbacktrace.style=raw -S rspec spec/ffi/io_spec.rb 
F

Failures:

  1) FFI::IO.for_fd produces an IO wrapping the specified file descriptor
     Failure/Error: Unable to find matching line from backtrace
       expected no Exception, got java.lang.UnsatisfiedLinkError: unknown
     # java/lang/Thread.java:1495:in `getStackTrace'

Finished in 0.084 seconds
1 example, 1 failure

Failed examples:

rspec ./spec/ffi/io_spec.rb:4 # FFI::IO.for_fd produces an IO wrapping the specified file descriptor
headius@headius-Server:~/jruby$ jruby -rffi -e "FFI::IO.for_fd(2)"
AsmRuntime.java:488:in `newUnsatisifiedLinkError': java.lang.UnsatisfiedLinkError: unknown
    from null:-1:in `fstat'
    from BaseNativePOSIX.java:101:in `fstat'
    from BaseNativePOSIX.java:90:in `fstat'
    from LazyPOSIX.java:95:in `fstat'
    from FileDescriptorIO.java:69:in `<init>'
    from FileDescriptorIO.java:100:in `newInstance'
    from FileDescriptorIO$INVOKER$s$1$0$newInstance.gen:-1:in `call'
    from CachingCallSite.java:326:in `cacheAndCall'
    from CachingCallSite.java:170:in `call'
    from CallOneArgNode.java:57:in `interpret'
    from NewlineNode.java:105:in `interpret'
    from ASTInterpreter.java:75:in `INTERPRET_METHOD'
    from InterpretedMethod.java:182:in `call'
    from DefaultMethod.java:188:in `call'
    from CachingCallSite.java:326:in `cacheAndCall'
    from CachingCallSite.java:170:in `call'
    from -e:1:in `__file__'
    from -e:-1:in `load'
    from Ruby.java:777:in `runScript'
    from Ruby.java:770:in `runScript'
    from Ruby.java:647:in `runNormally'
    from Ruby.java:496:in `runFromMain'
    from Main.java:375:in `doRunFromMain'
    from Main.java:264:in `internalRun'
    from Main.java:230:in `run'
    from Main.java:214:in `run'
    from Main.java:194:in `main'