How to find the IP of the system which shared my screen very last?
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in my office we can not set our own specific passwords for some systems since they are testing systems which can be used by anyone. 
The thing is, when i use the system some of my friends shares the screen and does some things and disconnects. I wanna know who is doing it. If i am sitting in front of the system then i can view the IP address of the system form which my screen is being shared. But when i am away, how can i find the IP address of the system which shared my screen? Is there any terminal commands for tht?? any applescripts? or any Plists??

Please let me know.

Thanks in advance.