оконечный мультиплексор (terminal multiplexer)
GLOBAL AND SESSION ENVIRONMENT
When the server is started, tmux copies the environment into the
global environment; in addition, each session has a session
environment. When a window is created, the session and global
environments are merged. If a variable exists in both, the value
from the session environment is used. The result is the initial
environment passed to the new process.
The update-environment session option may be used to update the
session environment from the client when a new session is created
or an old reattached. tmux also initialises the TMUX variable with
some internal information to allow commands to be executed from
inside, and the TERM variable with the correct terminal setting of
'screen'.
Variables in both session and global environments may be marked as
hidden. Hidden variables are not passed into the environment of
new processes and instead can only be used by tmux itself (for
example in formats, see the FORMATS section).
Commands to alter and view the environment are:
set-environment [-Fhgru] [-t target-session] name [value]
(alias: setenv)
Set or unset an environment variable. If -g is used, the
change is made in the global environment; otherwise, it is
applied to the session environment for target-session. If
-F is present, then value is expanded as a format. The -u
flag unsets a variable. -r indicates the variable is to be
removed from the environment before starting a new process.
-h marks the variable as hidden.
show-environment [-hgs] [-t target-session] [variable]
(alias: showenv)
Display the environment for target-session or the global
environment with -g. If variable is omitted, all variables
are shown. Variables removed from the environment are
prefixed with '-'. If -s is used, the output is formatted
as a set of Bourne shell commands. -h shows hidden
variables (omitted by default).
