Forums Scripts & Popups part script and join script

What would this join: join #chan1,#chan2 key1,key2 ?
chan1 with key1 and chan2 with key2
Yes exactly

join #chan1,#chan2 0,key2
to join #chan1 with 0 key (either 0 literally or no key and using the 0 as a placeholder) and #chan2 with key2

Technically this should work for the last... /join #chan1,#chan2 ,key2 ...but some ircds don't accept the empty parameter