The callers expected it to return an int different than 0 on failure. The
link method returns different than 0 on failure. This actually worked by
lucky coincidence. Change the return type to int and 0 on success, and -1
on failure per popular demand.
Thanks to Meisaka Yukara for spotting this.
Increase gid_t to an unsigned 64-bit integer.
Increase id_t to an unsigned 64-bit integer.
Increase pid_t to a signed 64-bit integer.
Increase time_t to a signed 64-bit integer.
Increase uid_t to an unsigned 64-bit integer.
Note: This is an incompatible ABI change.
The d_off field exists on other operating systems and the kernel used the
field in an incompatible manner. The easy solution is to call the field
something else and later address the design mistake.
