(This is actually a great interview question.) Having spent about 15 years doing C before discovering awk and then Perl, I feel qualified to say that you should be able to do just about everything you want to in Perl, with the exception being code that needs to run significantly faster than Perl -- and at that point you may be even better off by writing it in assembler.

An alternative that lies somewhere in the middle is to use Inline::C which will (or should) give you the best of both worlds -- the blazing speed of C, with the convenience of Perl. Although I can't say I've used this module, as far as I know, no makefile is required. It should take you just an hour or two to confirm that it works as advertised, and if you have problems, c'mon back here.