Store sessions in an RB tree by name rather than a list, this is tidier
and allows them to easily be shown sorted in various lists
(list-sessions/choose-sessions).
Keep a session index which is used in a couple of places internally but
make it an ever-increasing number rather than filling in gaps with new
sessions.
Change session and client activity and creation time members to have more
meaningful names.
Also, remove the code to try and update the session activity time for the
command client when a command message is received as is pointless because it
des not have a session.
Add "grouped sessions" which have independent name, options, current window and
so on but where the linked windows are synchronized (ie creating, killing
windows and so on are mirrored between the sessions). A grouped session may be
created by passing -t to new-session.
Had this around for a while, tested by a couple of people.
Make all messages sent between the client and server fixed size.
This is the first of two changes to make the protocol more resilient and less
sensitive to other changes in the code, particularly with commands. The client
now packs argv into a buffer and sends it to the server for parsing, rather
than doing it itself and sending the parsed command data.
As a side-effect this also removes a lot of now-unused command marshalling
code.
Mixing a server without this change and a client with or vice versa will cause
tmux to hang or crash, please ensure that tmux is entirely killed before
upgrading.
maintain and is only going to get worse as more are used. So instead, add a new
uint64_t member to cmd_entry which is a bitmask of upper and lowercase options
accepted by the command.
This means new single character options can be used without the need to add it
explicitly to the list.
