[9fans] [plan9mod] C compilers??

[qwertyp9q]

Just installed Plan 9 from a plan9.iso CD image.  However, once
installed tried running cc but that did not result in it being found
(nor 8c etc).  Tried google'ing and looking at the Plan 9 site but
have come up dry.  This seems to easy, so I'm sure I'm missing
something obvious.  Please help.  If there are any links to a download
that'll be necessary please provide, thanks.