A library originally developed under Linux to give userland programs
an API to access to USB hardware. The FreeBSD port was originally
done by Richard Tobin <richard@cogsci.ed.ac.uk> and should still
be considered "beta" (not all calls implemented in the Linux port
are available).  Allows gPhoto, gPhoto2, s10sh and others to access
USB under FreeBSD successfully.

WWW: http://sourceforge.net/projects/libusb/