Short answer: No, assuming you meant "should every CS senior know what a .tar file is?".
Long answer: Not always. Large and fascinating branches of CS has nothing to do with computers. A programmer looking to work on UNIX-based file systems should know what a .tar file is.
A commitment to GUI interfaces (and general mouse love) and not knowing .tar files probably just means the person had only seen Windows. I'd say the average child will take a week of dedicated learning before OK at using command line/Linux-based OS's. It would probably be a good idea to have a little intro-course to people who haven't seen Linux (kind of like a summary of OS class in college) at your company to catch these people up.
One of the things that bothers me most about the snobbier computer enthusiasts is how much pride they take in their curiosity, even if what they learn isn't all that impressive - it would take less than a minute to explain .tar file is to a degree more thorough than understood by half of the people who use them.
On the other hand, the CS program has a pretty glaring hole if it doesn't at least have an intro seminar into Unix-like operating systems, where things like tar files would surely be on the syllabus. I know I was offered a free week long seminar (about an hour a night) on Linux and gnu tools as a freshman at KU. Unix-like OS's make up a sizeable chunk of the programming landscape, so it would be strange to never mention them.
Maybe his CS program is super-theoretical and doesn't concern itself with implementation. Of course, it's far more likely that it's a lightweight shop turning out blub programmers.
Long answer: Not always. Large and fascinating branches of CS has nothing to do with computers. A programmer looking to work on UNIX-based file systems should know what a .tar file is.
A commitment to GUI interfaces (and general mouse love) and not knowing .tar files probably just means the person had only seen Windows. I'd say the average child will take a week of dedicated learning before OK at using command line/Linux-based OS's. It would probably be a good idea to have a little intro-course to people who haven't seen Linux (kind of like a summary of OS class in college) at your company to catch these people up.
One of the things that bothers me most about the snobbier computer enthusiasts is how much pride they take in their curiosity, even if what they learn isn't all that impressive - it would take less than a minute to explain .tar file is to a degree more thorough than understood by half of the people who use them.