Myself being a Linux/windows sys admin for 9 years, I have never come across a use case which I could not do with Perl. As far as sysadmin stuff is concerned, I don't really see a point learning c/c++. I have been doing perl automation for quite long and still explore new features of perl every now and then. On windows, I have used VB/batch/powershell and was able to automate the things. There were however few instances where I had to use python (I am a python noob). Definitely there is no need to work on c/c++ for **sys admin stuff**.