@(#)shared library howto 21 AUG 1997 Rob Thomas robt@cymru.com
Howto create a shared library with cc and ld.

Having always used ar(1) to create my libraries, I recently switched to
cc(1B) and ld(1) to create my shared libs.  Here's how:

1. Create as many C source files (.c) as required.  I created two:
   roblib01.c (with four funcs)
   roblib02.c (with four different funcs)

2. Compile the C source into object code thusly:
   pudge$ cc -c roblib0?.c
   You will now have four files, roblib0?.c and roblib0?.o

3. Now create your library with ld(1):
   pudge$ ld -o libRob.so -G roblib01.o roblib02.o
   -o is your output file option.
   -G in dynamic mode, produce a shared object (the goal!).

If you get unreferenced symbol errors, use lorder(1) to put your libs
in the correct order.  For example:

    ar -cr library `lorder *.o | tsort`

That's it!  Now link your library in with the -l option to ld.  Remember
to set your library path with -L, if necessary, to find your library.

As always, questions/comments/bugs to: robt@cymru.com

Rob Thomas, robt@cymru.com
http://www.enteract.com/~robt