GNATbl to Unix archive?

[gicca@alsys.com (Greg Gicca @pulsar)]

I have a program that provides an Ada interface to an existing utility
written in C and supplied as a Unix archive file.  I have ported
(mostly recompiled) the interface packages with GNAT.  How do I
specify the archive path and file name to "gnatbl".  I can see that
linker options can be passed on to "gcc" with "gnatbl", but I don't
know what the correct "gcc" ld option is.  I tried:
  -l/usr/lin/libsocket.a
  -llibsocket.a
  -lsocket
  -L (etc)
  -I (etc)
  L (etc)
  I (etc)
(The above is not the actual library I need but a reasonable
example.)

I am assuming something like:
   gnatbl -o unit unit.ali <the library parameter?>

Thanks in advance for any help.

Greg Gicca
Thomson Software Products
gicca@thomsoft.com