help

I have some questions about the design and implementation of the FreeBSD operating system 1. FreeBSD used System call, Hardware interrupt, Hardware trap, and Software-initiated trap to entry into the system kernel. What is the detailed operation and why FreeBSD design by this way? 2.

'help'

I have some question about the Design and the Implementation of the FreeBSD Operating System 1. FreeBSD used System call, Hardware interrupt, Hardware trap, and Software-initiated trap to entry into the system kernel. What is the detailed operation and why FreeBSD design by this way?