Everyone is correct about redirecting STDOUT and STDERR to the same place, but the key here is that he wants to close the terminal. In order to do that he needs to use the nohup command along with the '&' to put it in the background and disconnect from his controlling terminal session. When you use nohup it will write STDOUT and STDERR to a file in the working directory called "nohup.out" which you can then go back and get later (since you mention the C programs actually write to STDOUT and STDERR). You won't need the 2>&1, since nohup should handle that for you.

$ nohup ./perlthatcalls-c.pl &
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