Times from time should be stored in and treated as ulongs; this extends the range of valid times into the year 2106.

Time simply calls nsec and returns the value divided by 1000000000.

Nsec is a system call. Previous implementations read /dev/bintime, opening that file when first called, and maintaining a static file descriptor; however, the maintenance of file descriptors in the face of process forks is overly complex and prone to error.