https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=230624

This makes me a little sad, it's time to move to C++11 or greater.

Also stop using _exit(), believed unnecessary now with proper stdio
flushing.

As predicted, 'brew unlink python' is no longer needed.

This shouldn't require C++11 when not required.

This hack may not always detect when C++11 *is* required,
in which case a little autoconf tweaking may be needed
to get a good compile.

The 'brew unlink python' can probably be removed for later images.

Fixes #634.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

Fixes #946, matching the behavior of --server without --local.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

Use HAVE_UTEMPTER instead of HAVE_UPTEMPTER

Fix typo for issue #942:
- mosh-server incorrectly reports detached session in utmp/wtmp

10.10 is now obsolete, and installing packages from Homebrew on Travis
takes a long time because everything is built from source.

In moving this function from e2e-test, I forgot that it depends on a
variable set there.

This test is properly gated on tmux 2.4.

This reverts commit aa96fc86.

tmux doesn't support BCE until 2.4, so this change fails on 2.3.

Log connection change events to syslog in the auth log, logging the PID,
username and remote host.

Also log session begin and end.

Co-Authored-By: John Hood <cgull@glup.org>

Implement true color support define in:
https://en.wikipedia.org/wiki/ANSI_escape_code

The sequence is:
ESC[ … 38;2;;; … m Select RGB foreground color
ESC[ … 48;2;;; … m Select RGB background color

Signed-off-by: Anders Kaseorg <andersk@mit.edu>

This helps catch Perl syntax/version/dependency issues at build time
rather than run time.

A couple of them got improved out of existence.

(revert assert(false) added by 4835dcf5)
(fixes #918)