Do not assume dynamic linking in musl/mips targets

Add missing FreeBSD APIs

Process descriptors, realtime process priority, a couple missing kqueue event filters.

Add syscall table for musl/powerpc64

CI still runs version 10

Available since FreeBSD 9.0, this API allows using local descriptors
instead of global PIDs. It works in Capsicum sandboxes.

add DT_UNKNOWN

The `d_type` field of `struct dirent` can be `DT_UNKNOWN` if a
filesystem doesn't support returning the file type in directory entries.
Linux's readdir(3) man page, for example, says: "Currently, only some
filesystems [...] have full support for returning the file type in
d_type. All applications must properly handle a return of DT_UNKNOWN."

The `d_type` field of `struct dirent` can be `DT_UNKNOWN` if a
filesystem doesn't support returning the file type in directory entries.
Linux's readdir(3) man page, for example, says: "Currently, only some
filesystems [...] have full support for returning the file type in
d_type. All applications must properly handle a return of DT_UNKNOWN."

Bsd domainname

Closes #868 .

Fix containers using ubuntu 17.04

Apparently 17.04 has gone away? Or updates are failing now?

Looks like ubuntu 17.04 is broken now and it fails to link on 17.10 and 18.04.
It seems to work on stretch though!

Apparently 17.04 is broken now?

Closes #868 .

Add sockaddr_ctl on Mac

Add killpg

added EPOLL(5)  for Illumos (Solaris fork)

EPOLL(5)  is being used in crates like mio and iovec , this change allows those crates and other that depends on EPOLL(5)  to be built in illumos systems.

Difftime

Once merged, can you update the crate too please?

feat(linux): add mntent struct and related functions

Useful when playing around with mounting points, sadly not a common interface. :(

Useful when playing around with mounting points, sadly not a common
interface