The * modifier in regular expressions is "greedy". That means it will match the most that it possibly can. You can get a non-greedy match by adding ? after it like so: 

m/name="challenge" value="(.*?)"/

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Note that in general this won't cope with escaped quotes as in "* is \"greedy\" in regex". Before there were non-greedy matches, I might have written the expression this way (which also doesn't cope with escaped quotes): 

m/name="challenge" value="([^"]*)"/

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Or, given your input, this way (which will only match a hexadecimal string): 

m/name="challenge" value="([0-9a-f]+)"/

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As an aside, let me recommend in general using something like HTML::Parser when you're parsing HTML. Getting it right with regular expressions can be really difficult, but the module does the right thing for you.

In reply to Re: Regexp question by kyle
in thread Regexp question by davidov0009

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