Mac environment:
OS X Yosemite(10.10.5)

Command:
mono ~/msgpack-cli/tools/mpu/bin/mpu.exe -h

Output of mpu.exe:
WARNING: The runtime version supported by this application is unavailable.
Using default runtime: v4.0.30319
MessagePack for Unity Utility ver. 0.6.5

....

Exit code:
0: success
1: help is shown
2: invalid arguments
0x57-0xFE: other errors
0xFF: other errors its hresult is gerator than 0xFE

What is runtime to be concrete?

I want to make the following command.
mono /msgpack-cli/tools/mpu/bin/mpu.exe -l -o </***>
*** is any hierarchy.

However, the output is following:
System.IO.FileNotFoundException: Could not load file or assembly 'MsgPack, Version=0.6.0.0, Culture=neutral, PublicKeyToken=a2625990d5dc0167' or one of its dependencies.
File name: 'MsgPack, Version=0.6.0.0, Culture=neutral, PublicKeyToken=a2625990d5dc0167'
at mpu.Program.Main (System.String[] args) [0x00000] in :0

Thanks,