Others have answered your question. Basically you have three different types of question marks: ?:, \? and ? - non capturing matching, escaping, and zero or more matches. But looking at that regex, I wonder if it's all just overkill. It looks like your matching a flash url that may have paramaters. I wonder if this simpler regex will do the job as well: 

m/\.swf.*$/oi

[download]
Comments? I know some people wish death to dot-star but what's the downside here?

-derby

In reply to Re: questions of a perl beginner on regex by derby
in thread questions of a perl beginner on regex by jithoosin

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