on *:join:#channel1,#channel2,#channel3:/whois $nick

replace #channel1,#channel2,#channel3 with your real channel names

or, if you have it inside of another script:

Code:
on *:join:#: {
  if (($chan == #channel1) || ($chan == #channel2) || ($chan == #channel3)) { whois $nick }
}


or you could even do this (by filling in the variable with a channel's name separated by a comma):

Code:
on *:join:#: {
  if (#chan isin %whoischannel) { whois $nick }
}



Hope that helps


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