slave identification

We are about to work over some code written last Jan-May with the then current version of libmodbus.

I find these files on my machine with Apr 24 modification dates:

/usr/local/libmodbus.so.2.0.0
/usr/local/lib/libmodbus.la
/usr/local/lib/libmodbus.so
/usr/local/lib/libmodbus.so.2
/usr/local/lib/libmodbus.so.2.0.0

Are we likely to experience any glitches when we switch to the most recent libmodbus?

In particular, I remember some discussion, that I cannot locate at the moment, about additional parameters relating to slave number/identity . The code we will work on includes a couple of lines in the TCP and serial interface routines that discards queries to other slaves. Is this still necessary or is there another way? I may have missed features that were available the first time around.

Thanks,

John Carroll