Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Even though POSIX allows us to return simply /dev/tty as a pathname
identifying the controlling terminal of the running process, it is nicer
if this function were actually useful, by returning the actual pathname
of the controlling terminal.
Implement ctermid() by using the kern.devname sysctl to resolve the
actual name of /dev/tty. Don't use devname(3), since it may return bogus
strings like #C:0x123.
