It is a portable version of the realpath(1) utility that you can find on
Mac OS X and FreeBSD (see also The Open Group Base Specifications Issue
6, IEEE Std 1003.1).

Without the -P flag, pwd(1) might return different values when the
current path contains one or more symlinks, depending on how you got
into the current directory.

In simplenode.runner, this may cause PIPE_DIR to have different values
on each use, which will make it impossible to connect to the running
node unless you guess the correct path yourself.

When developing Riak, we have found bugs and other issues due
to the number of platforms we support.

Here is an overview of the changes:
  -  Fix command-line syntax for commands to work on *BSD / Sun
  -  Add chkconfig and getpid to nodetool
  -  Replace platform specific 'kill' commands with a nodetool
	getpid method
  -  Fix RUNNER_USER settings to work on *BSD