gopbo is a free and open source tool to (un)pack/validate PBO files written in Go. The tool doesn't depend on any platform specific functions. Thus it should run on every platform which is supported by Go.
First you need to install the Go Tools.
After the Go Tools have been installed you should set the environment variable GOPATH to point wherever you want to. Also you may want to add /bin to your PATH.
go get -u github.com/g0dsCookie/gopbo
go install github.com/g0dsCookie/gopbo
Now you are ready to use gopbo!