liblo is a easy to use OSC (Open Sound Control) implementation written in C.
http://plugin.org.uk/liblo/
See the website for docs and example code.
Changes since last release:
        bugfixes
        OSC URL handling
        better IPV6 support
        real documentation
        better example code
        support for all the types listed in the specification
        automatic port number selection for servers
        lo_target type has been deprecated, use lo_address now
        some buffer overrun checks in lo_send()
This version is not binary compatible with the previous release.
- Steve