Is the output of meta available for use in my program?

Yes. meta’s result is an ordinary q table:

$ rlwrap q sp.q
KDB+ 2.7 2011.02.16 Copyright © 1993-2011 Kx Systems
q)type meta sp
q)meta sp
c  | t f a
---| -----
s  | s s
p  | s p
qty| i
q)cols meta sp
q)meta meta sp
c| t f a
-| -----
c| s
t| c
f| s
a| s