Returning part of a string, ereg..

I'm horrible at regex's, maybe someone can help me out. What I'm trying to do is parse a string in the format: number-number-number (ex. 1-23123-312039128) I need to pull that second number, regardless of length This code returns nothing: $part = ereg("([0-9]{1})-([0-9])-", $f, $regs); but $part = ereg("([0-9]{1})-([0-9]{1,10})-", $f, $regs); will return the number, but I don't want to take a chance and limit it to 10 characters. I thought the first bit of code would work.. any ideas what is wrong? Thanks, Chad