If you die() or exit () in an eval block, the error goes to $! (or is it $@?) and the eval returns false. It's like Java's try/catch. If you die on not having success you can test for that. If, on the other hand, you mean that LWP::UserAgent is printing to STDERR, and you want to stop it, just redirect STDERR -- i.e. open ("STDERR", "> ./error").
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