I use `runas /user:abc cmd` to start a command prompt. After login, I will run a vbs script.

The login abc has special file/folder permission, and it is the main reason for using runas. Otherwise the vbs script will not work due to lack of permission

Inside this command prompt session, how can I obtain the username which started the runas command? I want to log this information inside my vbs script. 

As an example, let's say my id is 'akong'. After I started command prompt as 'abc' with runas, I want to be able print out 'akong' one way or another.