Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Teach fifo_create regression test to also try to use mknod(2) to create
fifos, as this is required by the Single UNIX Specification, although
not currently implemented on FreeBSD.

While here, fix a bug in the directory timestamp checking test by
sleeping after querying the starting timestamp, rather than before.

o style.Makefile(5): WARNS= -> WARNS?=.

Add fifo_create, a simple regression test for mkfifo(2).