TMUX(1)                    OpenBSD Reference Manual                    TMUX(1)

NAME
     tmux - terminal multiplexer

SYNOPSIS
     tmux [-28lquv] [-c shell-command] [-f file] [-L socket-name]
          [-S socket-path] [command [flags]]

DESCRIPTION
     tmux is a terminal multiplexer: it enables a number of terminals to be
     created, accessed, and controlled from a single screen.  tmux may be de-
     tached from a screen and continue running in the background, then later
     reattached.

     When tmux is started it creates a new session with a single window and
     displays it on screen.  A status line at the bottom of the screen shows
     information on the current session and is used to enter interactive com-
     mands.

     A session is a single collection of pseudo terminals under the management
     of tmux.  Each session has one or more windows linked to it.  A window
     occupies the entire screen and may be split into rectangular panes, each
     of which is a separate pseudo terminal (the pty(4) manual page documents
     the technical details of pseudo terminals).  Any number of tmux instances
     may connect to the same session, and any number of windows may be present
     in the same session.  Once all sessions are killed, tmux exits.

     Each session is persistent and will survive accidental disconnection
     (such as ssh(1) connection timeout) or intentional detaching (with the
     `C-b d' key strokes).  tmux may be reattached using:

           $ tmux attach

     In tmux, a session is displayed on screen by a client and all sessions
     are managed by a single server.  The server and each client are separate
     processes which communicate through a socket in /tmp.

     The options are as follows:

     -2            Force tmux to assume the terminal supports 256 colours.

     -8            Like -2, but indicates that the terminal supports 88
                   colours.

     -c shell-command
                   Execute shell-command using the default shell.  If neces-
                   sary, the tmux server will be started to retrieve the
                   default-shell option.  This option is for compatibility
                   with sh(1) when tmux is used as a login shell.

     -f file       Specify an alternative configuration file.  By default,
                   tmux loads the system configuration file from
                   /etc/tmux.conf, if present, then looks for a user configu-
                   ration file at ~/.tmux.conf.  The configuration file is a
                   set of tmux commands which are executed in sequence when
                   the server is first started.

                   If a command in the configuration file fails, tmux will re-
                   port an error and exit without executing further commands.

     -l            Behave as a login shell.  This flag currently has no effect
                   and is for compatibility with other shells when using tmux
                   as a login shell.

     -L socket-name
                   tmux stores the server socket in a directory under /tmp;
                   the default socket is named default.  This option allows a
                   different socket name to be specified, allowing several in-
                   dependent tmux servers to be run.  Unlike -S a full path is
                   not necessary: the sockets are all created in the same di-
                   rectory.

                   If the socket is accidentally removed, the SIGUSR1 signal
                   may be sent to the tmux server process to recreate it.

     -q            Set the quiet server option to prevent the server sending
                   various informational messages.

     -S socket-path
                   Specify a full alternative path to the server socket.  If
                   -S is specified, the default socket directory is not used
                   and any -L flag is ignored.

     -u            tmux attempts to guess if the terminal is likely to support
                   UTF-8 by checking the first of the LC_ALL, LC_CTYPE and
                   LANG environment variables to be set for the string
                   "UTF-8".  This is not always correct: the -u flag explicit-
                   ly informs tmux that UTF-8 is supported.

                   If the server is started from a client passed -u or where
                   UTF-8 is detected, the utf8 and status-utf8 options are en-
                   abled in the global window and session options respective-
                   ly.

     -v            Request verbose logging.  This option may be specified mul-
                   tiple times for increasing verbosity.  Log messages will be
                   saved into tmux-client-PID.log and tmux-server-PID.log
                   files in the current directory, where PID is the PID of the
                   server or client process.

     command [flags]
                   This specifies one of a set of commands used to control
                   tmux, as described in the following sections.  If no com-
                   mands are specified, the new-session command is assumed.

KEY BINDINGS
     tmux may be controlled from an attached client by using a key combination
     of a prefix key, `C-b' (Ctrl-b) by default, followed by a command key.

     Some of the default key bindings are:

           c       Create a new window.
           d       Detach the current client.
           l       Move to the previously selected window.
           n       Change to the next window.
           p       Change to the previous window.
           &       Kill the current window.
           ,       Rename the current window.
           ?       List all key bindings.

     A complete list may be obtained with the list-keys command (bound to `?'
     by default).  Key bindings may be changed with the bind-key and unbind-
     key commands.

COMMANDS
     This section contains a list of the commands supported by tmux.  Most
     commands accept the optional -t argument with one of target-client,
     target-session target-window, or target-pane.  These specify the client,
     session, window or pane which a command should affect.  target-client is
     the name of the pty(4) file to which the client is connected, for example
     either of /dev/ttyp1 or ttyp1 for the client attached to /dev/ttyp1.  If
     no client is specified, the current client is chosen, if possible, or an
     error is reported.  Clients may be listed with the list-clients command.

     target-session is either the name of a session (as listed by the list-
     sessions command) or the name of a client with the same syntax as target-
     client, in which case the session attached to the client is used.  When
     looking for the session name, tmux initially searches for an exact match;
     if none is found, the session names are checked for any for which target-
     session is a prefix or for which it matches as an fnmatch(3) pattern.  If
     a single match is found, it is used as the target session; multiple
     matches produce an error.  If a session is omitted, the current session
     is used if available; if no current session is available, the most re-
     cently used is chosen.

     target-window specifies a window in the form session:window.  session
     follows the same rules as for target-session, and window is looked for in
     order: as a window index, for example mysession:1; as an exact window
     name, such as mysession:mywindow; then as an fnmatch(3) pattern or the
     start of a window name, such as mysession:mywin* or mysession:mywin.  An
     empty window name specifies the next unused index if appropriate (for ex-
     ample the new-window and link-window commands) otherwise the current win-
     dow in session is chosen.  The special character `!' uses the last (pre-
     viously current) window, or `+' and `-' are the next window or the previ-
     ous window by number.  When the argument does not contain a colon, tmux
     first attempts to parse it as window; if that fails, an attempt is made
     to match a session.

     target-pane takes a similar form to target-window but with the optional
     addition of a period followed by a pane index, for example: mysession:my-
     window.1.  If the pane index is omitted, the currently active pane in the
     specified window is used.  If neither a colon nor period appears, tmux
     first attempts to use the argument as a pane index; if that fails, it is
     looked up as for target-window.  One of the strings top, bottom, left,
     right, top-left, top-right, bottom-left or bottom-right may be used in-
     stead of a pane index.

     shell-command arguments are sh(1) commands.  These must be passed as a
     single item, which typically means quoting them, for example:

           new-window 'vi /etc/passwd'

     command [arguments] refers to a tmux command, passed with the command and
     arguments separately, for example:

           bind-key F1 set-window-option force-width 81

     Or if using sh(1):

           $ tmux bind-key F1 set-window-option force-width 81

     Multiple commands may be specified together as part of a command
     sequence.  Each command should be separated by spaces and a semicolon;
     commands are executed sequentially from left to right.  A literal semi-
     colon may be included by escaping it with a backslash (for example, when
     specifying a command sequence to bind-key).

     Example tmux commands include:

           refresh-client -t/dev/ttyp2

           rename-session -tfirst newname

           set-window-option -t:0 monitor-activity on

           new-window ; split-window -d

     Or from sh(1):

           $ tmux kill-window -t :1

           $ tmux new-window \; split-window -d

           $ tmux new-session -d 'vi /etc/passwd' \; split-window -d \; attach

CLIENTS AND SESSIONS
     The tmux server manages clients, sessions, windows and panes.  Clients
     are attached to sessions to interact with them, either when they are cre-
     ated with the new-session command, or later with the attach-session com-
     mand.  Each session has one of more windows linked into it.  Windows may
     be linked to multiple sessions and are made up of one or more panes, each
     of which contains a pseudo terminal.  Commands for creating, linking and
     otherwise manipulating windows are covered in the WINDOWS AND PANES sec-
     tion.

     The following commands are available to manage clients and sessions:

     attach-session [-dr] [-t target-session]
                   (alias: attach)
             If run from outside tmux, create a new client in the current ter-
             minal and attach it to target-session.  If used from inside,
             switch the current client.  If -d is specified, any other clients
             attached to the session are detached.  -r signifies the client is
             read-only (only keys bound to the detach-client command have any
             effect)

             If no server is started, attach-session will attempt to start it;
             this will fail unless sessions are created in the configuration
             file.

     detach-client [-t target-client]
                   (alias: detach)
             Detach the current client if bound to a key, or the specified
             client with -t.

     has-session [-t target-session]
                   (alias: has)
             Report an error and exit with 1 if the specified session does not
             exist.  If it does exist, exit with 0.

     kill-server
             Kill the tmux server and clients and destroy all sessions.

     kill-session [-t target-session]
             Destroy the given session, closing any windows linked to it and
             no other sessions, and detaching all clients attached to it.

     list-clients
                   (alias: lsc)
             List all clients attached to the server.

     list-commands
                   (alias: lscm)
             List the syntax of all commands supported by tmux.

     list-sessions
                   (alias: ls)
             List all sessions managed by the server.

     lock-client [-t target-client]
             Lock target-client, see the lock-server command.

     lock-session [-t target-session]
             Lock all clients attached to target-session.

     new-session [-d] [-n window-name] [-s session-name] [-t target-session]
             [shell-command]
                   (alias: new)
             Create a new session with name session-name.

             The new session is attached to the current terminal unless -d is
             given.  window-name and shell-command are the name of and shell
             command to execute in the initial window.

             If run from a terminal, any termios(4) special characters are
             saved and used for new windows in the new session.

             If -t is given, the new session is grouped with target-session.
             This means they share the same set of windows - all windows from
             target-session are linked to the new session and any subsequent
             new windows or windows being closed are applied to both sessions.
             The current and previous window and any session options remain
             independent and either session may be killed without affecting
             the other.  Giving -n or shell-command are invalid if -t is used.

     refresh-client [-t target-client]
                   (alias: refresh)
             Refresh the current client if bound to a key, or a single client
             if one is given with -t.

     rename-session [-t target-session] new-name
                   (alias: rename)
             Rename the session to new-name.

     show-messages [-t target-client]
                   (alias: showmsgs)
             Any messages displayed on the status line are saved in a per-
             client message log, up to a maximum of the limit set by the
             message-limit session option for the session attached to that
             client.  This command displays the log for target-client.

     source-file path
                   (alias: source)
             Execute commands from path.

     start-server
                   (alias: start)
             Start the tmux server, if not already running, without creating
             any sessions.

     suspend-client [-c target-client]
                   (alias: suspendc)
             Suspend a client by sending SIGTSTP (tty stop).

     switch-client [-c target-client] [-t target-session]
                   (alias: switchc)
             Switch the current session for client target-client to target-
             session.

WINDOWS AND PANES
     A tmux window may be in one of several modes.  The default permits direct
     access to the terminal attached to the window.  The others are:

     output mode
             This is entered when a command which produces output, such as
             list-keys, is executed from a key binding.

     copy mode
             This permits a section of a window or its history to be copied to
             a paste buffer for later insertion into another window.  This
             mode is entered with the copy-mode command, bound to `[' by de-
             fault.

     The keys available depend on whether emacs or vi mode is selected (see
     the mode-keys option).  The following keys are supported as appropriate
     for the mode:

           Function                  vi              emacs
           Back to indentation       ^               M-m
           Bottom of history         G               M-<
           Clear selection           Escape          C-g
           Copy selection            Enter           M-w
           Cursor down               j               Down
           Cursor left               h               Left
           Cursor right              l               Right
           Cursor to bottom line     L
           Cursor to middle line     M               M-r
           Cursor to top line        H               M-R
           Cursor up                 k               Up
           Delete entire line        d               C-u
           Delete to end of line     D               C-k
           End of line               $               C-e
           Go to line                :               g
           Half page down            C-d             M-Down
           Half page up              C-u             M-Up
           Next page                 C-f             Page down
           Next space                W
           Next space, end of word   E
           Next word                 w
           Next word end             e               M-f
           Paste buffer              p               C-y
           Previous page             C-b             Page up
           Previous word             b               M-b
           Previous space            B
           Quit mode                 q               Escape
           Rectangle toggle          v               R
           Scroll down               C-Down or C-e   C-Down
           Scroll up                 C-Up or C-y     C-Up
           Search again              n               n
           Search again in reverse   N               N
           Search backward           ?               C-r
           Search forward            /               C-s
           Start of line             0               C-a
           Start selection           Space           C-Space
           Top of history            g               M->
           Transpose chars                           C-t

     The next and previous word keys use space and the `-', `_' and `@' char-
     acters as word delimiters by default, but this can be adjusted by setting
     the word-separators window option.  Next word moves to the start of the
     next word, next word end to the end of the next word and previous word to
     the start of the previous word.  The three next and previous space keys
     work similarly but use a space alone as the word separator.

     Commands in copy mode may be prefaced by an optional repeat count.  With
     vi key bindings, a prefix is entered using the number keys; with emacs,
     the Alt (meta) key and a number begins prefix entry.  For example, to
     move the cursor forward by ten words, use `M-1 0 M-f' in emacs mode, and
     `10w' in vi.

     Mode key bindings are defined in a set of named tables: vi-edit and
     emacs-edit for keys used when line editing at the command prompt; vi-
     choice and emacs-choice for keys used when choosing from lists (such as
     produced by the choose-window command) or in output mode; and vi-copy and
     emacs-copy used in copy mode.  The tables may be viewed with the list-
     keys command and keys modified or removed with bind-key and unbind-key.

     The paste buffer key pastes the first line from the top paste buffer on
     the stack.

     The mode commands are as follows:

     copy-mode [-u] [-t target-pane]
             Enter copy mode.  The -u option scrolls one page up.

     Each window displayed by tmux may be split into one or more panes; each
     pane takes up a certain area of the display and is a separate terminal.
     A window may be split into panes using the split-window command.  Windows
     may be split horizontally (with the -h flag) or vertically.  Panes may be
     resized with the resize-pane command (bound to `C-up', `C-down' `C-left'
     and `C-right' by default), the current pane may be changed with the up-
     pane and down-pane commands and the rotate-window and swap-pane commands
     may be used to swap panes without changing their position.  Panes are
     numbered beginning from zero in the order they are created.

     A number of preset layouts are available.  These may be selected with the
     select-layout command or cycled with next-layout (bound to `Space' by de-
     fault); once a layout is chosen, panes within it may be moved and resized
     as normal.

     The following layouts are supported:

     even-horizontal
             Panes are spread out evenly from left to right across the window.

     even-vertical
             Panes are spread evenly from top to bottom.

     main-horizontal
             A large (main) pane is shown at the top of the window and the re-
             maining panes are spread from left to right in the leftover space
             at the bottom.  Use the main-pane-height window option to specify
             the height of the top pane.

     main-vertical
             Similar to main-horizontal but the large pane is placed on the
             left and the others spread from top to bottom along the right.
             See the main-pane-width window option.

     Commands related to windows and panes are as follows:

     break-pane [-d] [-t target-pane]
                   (alias: breakp)
             Break target-pane off from its containing window to make it the
             only pane in a new window.  If -d is given, the new window does
             not become the current window.

     capture-pane [-b buffer-index] [-t target-pane]
                   (alias: capturep)
             Capture the contents of a pane to the specified buffer, or a new
             buffer if none is specified.

     choose-client [-t target-window] [template]
             Put a window into client choice mode, allowing a client to be se-
             lected interactively from a list.  After a client is chosen, `%%'
             is replaced by the client pty(4) path in template and the result
             executed as a command.  If template is not given, "detach-client
             -t '%%'" is used.  This command works only from inside tmux.

     choose-session [-t target-window] [template]
             Put a window into session choice mode, where a session may be se-
             lected interactively from a list.  When one is chosen, `%%' is
             replaced by the session name in template and the result executed
             as a command.  If template is not given, "switch-client -t '%%'"
             is used.  This command works only from inside tmux.

     choose-window [-t target-window] [template]
             Put a window into window choice mode, where a window may be cho-
             sen interactively from a list.  After a window is selected, `%%'
             is replaced by the session name and window index in template and
             the result executed as a command.  If template is not given, "se-
             lect-window -t '%%'" is used.  This command works only from in-
             side tmux.

     display-panes [-t target-client]
                   (alias: displayp)
             Display a visible indicator of each pane shown by target-client.
             See the display-panes-time, display-panes-colour, and display-
             panes-active-colour session options.  While the indicator is on
             screen, a pane may be selected with the `0' to `9' keys.

     down-pane [-t target-pane]
                   (alias: downp)
             Change the active pane to the next pane (higher index).

     find-window [-t target-window] match-string
                   (alias: findw)
             Search for the fnmatch(3) pattern match-string in window names,
             titles, and visible content (but not history).  If only one win-
             dow is matched, it'll be automatically selected, otherwise a
             choice list is shown.  This command only works from inside tmux.

     join-pane [-dhv] [-l size | -p percentage] [-s src-pane] [-t dst-pane]
                   (alias: joinp)
             Like split-window, but instead of splitting dst-pane and creating
             a new pane, split it and move src-pane into the space.  This can
             be used to reverse break-pane.

     kill-pane [-a] [-t target-pane]
                   (alias: killp)
             Destroy the given pane.  If no panes remain in the containing
             window, it is also destroyed.  The -a option kills all but the
             pane given with -t.

     kill-window [-t target-window]
                   (alias: killw)
             Kill the current window or the window at target-window, removing
             it from any sessions to which it is linked.

     last-window [-t target-session]
                   (alias: last)
             Select the last (previously selected) window.  If no target-
             session is specified, select the last window of the current ses-
             sion.

     link-window [-dk] [-s src-window] [-t dst-window]
                   (alias: linkw)
             Link the window at src-window to the specified dst-window.  If
             dst-window is specified and no such window exists, the src-window
             is linked there.  If -k is given and dst-window exists, it is
             killed, otherwise an error is generated.  If -d is given, the
             newly linked window is not selected.

     list-panes [-t target-window]
                   (alias: lsp)
             List the panes in the current window or in target-window.

     list-windows [-t target-session]
                   (alias: lsw)
             List windows in the current session or in target-session.

     move-window [-d] [-s src-window] [-t dst-window]
                   (alias: movew)
             This is similar to link-window, except the window at src-window
             is moved to dst-window.

     new-window [-dk] [-n window-name] [-t target-window] [shell-command]
                   (alias: neww)
             Create a new window.  If -d is given, the session does not make
             the new window the current window.  target-window represents the
             window to be created; if the target already exists an error is
             shown, unless the -k flag is used, in which case it is destroyed.
             shell-command is the command to execute.  If shell-command is not
             specified, the value of the default-command option is used.

             When the shell command completes, the window closes.  See the
             remain-on-exit option to change this behaviour.

             The TERM environment variable must be set to ``screen'' for all
             programs running inside tmux.  New windows will automatically
             have ``TERM=screen'' added to their environment, but care must be
             taken not to reset this in shell start-up files.

     next-layout [-t target-window]
                   (alias: nextl)
             Move a window to the next layout and rearrange the panes to fit.

     next-window [-a] [-t target-session]
                   (alias: next)
             Move to the next window in the session.  If -a is used, move to
             the next window with a bell, activity or content alert.

     pipe-pane [-o] [-t target-pane] [shell-command]
                   (alias: pipep)
             Pipe any output sent by the program in target-pane to a shell
             command.  A pane may only be piped to one command at a time, any
             existing pipe is closed before shell-command is executed.  If no
             shell-command is given, the current pipe (if any) is closed.

             The -o option only opens a new pipe if no previous pipe exists,
             allowing a pipe to be toggled with a single key, for example:

                   bind-key C-p pipe-pane -o 'cat >>~/output'

     previous-window [-a] [-t target-session]
                   (alias: prev)
             Move to the previous window in the session.  With -a, move to the
             previous window with a bell, activity or content alert.

     rename-window [-t target-window] new-name
                   (alias: renamew)
             Rename the current window, or the window at target-window if
             specified, to new-name.

     resize-pane [-DLRU] [-t target-pane] [adjustment]
                   (alias: resizep)
             Resize a pane, upward with -U (the default), downward with -D, to
             the left with -L and to the right with -R.  The adjustment is
             given in lines or cells (the default is 1).

     respawn-window [-k] [-t target-window] [shell-command]
                   (alias: respawnw)
             Reactivate a window in which the command has exited (see the
             remain-on-exit window option).  If shell-command is not given,
             the command used when the window was created is executed.  The
             window must be already inactive, unless -k is given, in which
             case any existing command is killed.

     rotate-window [-DU] [-t target-window]
                   (alias: rotatew)
             Rotate the positions of the panes within a window, either upward
             (numerically lower) with -U or downward (numerically higher).

     select-layout [-t target-window] [layout-name]
                   (alias: selectl)
             Choose a specific layout for a window.  If layout-name is not
             given, the last layout used (if any) is reapplied.

     select-pane [-t target-pane]
                   (alias: selectp)
             Make pane target-pane the active pane in window target-window.

     select-window [-t target-window]
                   (alias: selectw)
             Select the window at target-window.

     split-window [-dhv] [-l size | -p percentage] [-t target-pane]
             [shell-command]
                   (alias: splitw)
             Create a new pane by splitting target-pane: -h does a horizontal
             split and -v a vertical split; if neither is specified, -v is as-
             sumed.  The -l and -p options specify the size of the new pane in
             lines (for vertical split) or in cells (for horizontal split), or
             as a percentage, respectively.  All other options have the same
             meaning as for the new-window command.

     swap-pane [-dDU] [-s src-pane] [-t dst-pane]
                   (alias: swapp)
             Swap two panes.  If -U is used and no source pane is specified
             with -s, dst-pane is swapped with the previous pane (before it
             numerically); -D swaps with the next pane (after it numerically).
             -d instructs tmux not to change the active pane.

     swap-window [-d] [-s src-window] [-t dst-window]
                   (alias: swapw)
             This is similar to link-window, except the source and destination
             windows are swapped.  It is an error if no window exists at src-
             window.

     unlink-window [-k] [-t target-window]
                   (alias: unlinkw)
             Unlink target-window.  Unless -k is given, a window may be un-
             linked only if it is linked to multiple sessions - windows may
             not be linked to no sessions; if -k is specified and the window
             is linked to only one session, it is unlinked and destroyed.

     up-pane [-t target-pane]
                   (alias: upp)
             Change the active pane to the previous pane (lower index).

KEY BINDINGS
     tmux allows a command to be bound to most keys, with or without a prefix
     key.  When specifying keys, most represent themselves (for example `A' to
     `Z').  Ctrl keys may be prefixed with `C-' or `^', and Alt (meta) with
     `M-'.  In addition, the following special key names are accepted: Up,
     Down, Left, Right, BSpace, BTab, DC (Delete), End, Enter, Escape, F1 to
     F20, Home, IC (Insert), NPage (Page Up), PPage (Page Down), Space, and
     Tab.  Note that to bind the `"' or `'' keys, quotation marks are neces-
     sary, for example:

           bind-key '"' split-window
           bind-key "'" select-prompt

     Commands related to key bindings are as follows:

     bind-key [-cnr] [-t key-table] key command [arguments]
                   (alias: bind)
             Bind key key to command.  By default (without -t) the primary key
             bindings are modified (those normally activated with the prefix
             key); in this case, if -n is specified, it is not necessary to
             use the prefix key, command is bound to key alone.  The -r flag
             indicates this key may repeat, see the repeat-time option.

             If -t is present, key is bound in key-table: the binding for com-
             mand mode with -c or for normal mode without.  To view the de-
             fault bindings and possible commands, see the list-keys command.

     list-keys [-t key-table]
                   (alias: lsk)
             List all key bindings.  Without -t the primary key bindings -
             those executed when preceded by the prefix key - are printed.
             Keys bound without the prefix key (see bind-key -n) are marked
             with `(no prefix)'.

             With -t, the key bindings in key-table are listed; this may be
             one of: vi-edit, emacs-edit, vi-choice, emacs-choice, vi-copy or
             emacs-copy.

     send-keys [-t target-pane] key ...
                   (alias: send)
             Send a key or keys to a window.  Each argument key is the name of
             the key (such as `C-a' or `npage' ) to send; if the string is not
             recognised as a key, it is sent as a series of characters.  All
             arguments are sent sequentially from first to last.

     send-prefix [-t target-pane]
             Send the prefix key to a window as if it was pressed.  If multi-
             ple prefix keys are configured, only the first is sent.

     unbind-key [-cn] [-t key-table] key
                   (alias: unbind)
             Unbind the command bound to key.  Without -t the primary key
             bindings are modified; in this case, if -n is specified, the com-
             mand bound to key without a prefix (if any) is removed.

             If -t is present, key in key-table is unbound: the binding for
             command mode with -c or for normal mode without.

OPTIONS
     The appearance and behaviour of tmux may be modified by changing the val-
     ue of various options.  There are three types of option: server options,
     session options and window options.

     The tmux server has a set of global options which do not apply to any
     particular window or session.  These are altered with the set-option -s
     command, or displayed with the show-options -s command.

     In addition, each individual session may have a set of session options,
     and there is a separate set of global session options.  Sessions which do
     not have a particular option configured inherit the value from the global
     session options.  Session options are set or unset with the set-option
     command and may be listed with the show-options command.  The available
     server and session options are listed under the set-option command.

     Similarly, a set of window options is attached to each window, and there
     is a set of global window options from which any unset options are inher-
     ited.  Window options are altered with the set-window-option command and
     can be listed with the show-window-options command.  All window options
     are documented with the set-window-option command.

     Commands which set options are as follows:

     set-option [-agsuw] [-t target-session | target-window] option value
                   (alias: set)
             Set a window option with -w (equivalent to the set-window-option
             command), a server option with -s, otherwise a session option.

             If -g is specified, the global session or window option is set.
             With -a, and if the option expects a string, value is appended to
             the existing setting.  The -u flag unsets an option, so a session
             inherits the option from the global options.  It is not possible
             to unset a global option.

             Available window options are listed under set-window-option.

             Available server options are:

             escape-time
                     Set the time in milliseconds for which tmux waits after
                     an escape is input to determine if it is part of a func-
                     tion or meta key sequences.  The default is 500 millisec-
                     onds.

             quiet   Enable or disable the display of various informational
                     messages (see also the -q command line flag).

             Available session options are:

             base-index index
                     Set the base index from which an unused index should be
                     searched when a new window is created.  The default is
                     zero.

             bell-action [any | none | current]
                     Set action on window bell.  any means a bell in any win-
                     dow linked to a session causes a bell in the current win-
                     dow of that session, none means all bells are ignored and
                     current means only bell in windows other than the current
                     window are ignored.

             buffer-limit number
                     Set the number of buffers kept for each session; as new
                     buffers are added to the top of the stack, old ones are
                     removed from the bottom if necessary to maintain this
                     maximum length.

             default-command shell-command
                     Set the command used for new windows (if not specified
                     when the window is created) to shell-command, which may
                     be any sh(1) command.  The default is an empty string,
                     which instructs tmux to create a login shell using the
                     value of the default-shell option.

             default-shell path
                     Specify the default shell.  This is used as the login
                     shell for new windows when the default-command option is
                     set to empty, and must be the full path of the exe-
                     cutable.  When started tmux tries to set a default value
                     from the first suitable of the SHELL environment vari-
                     able, the shell returned by getpwuid(3), or /bin/sh.
                     This option should be configured when tmux is used as a
                     login shell.

             default-path path
                     Set the default working directory for processes created
                     from keys, or interactively from the prompt.  The default
                     is the current working directory when the server is
                     started.

             default-terminal terminal
                     Set the default terminal for new windows created in this
                     session - the default value of the TERM environment vari-
                     able.  For tmux to work correctly, this must be set to
                     `screen' or a derivative of it.

             display-panes-active-colour colour
                     Set the colour used by the display-panes command to show
                     the indicator for the active pane.

             display-panes-colour colour
                     Set the colour used by the display-panes command to show
                     the indicators for inactive panes.

             display-panes-time time
                     Set the time in milliseconds for which the indicators
                     shown by the display-panes command appear.

             display-time time
                     Set the amount of time for which status line messages and
                     other on-screen indicators are displayed.  time is in
                     milliseconds.

             history-limit lines
                     Set the maximum number of lines held in window history.
                     This setting applies only to new windows - existing win-
                     dow histories are not resized and retain the limit at the
                     point they were created.

             lock-after-time number
                     Lock the session (like the lock-session command) after
                     number seconds of inactivity, or the entire server (all
                     sessions) if the lock-server option is set.  The default
                     is not to lock (set to 0).

             lock-command shell-command
                     Command to run when locking each client.  The default is
                     to run lock(1) with -np.

             lock-server [on | off]
                     If this option is on (the default), instead of each ses-
                     sion locking individually as each has been idle for lock-
                     after-time, the entire server will lock after all ses-
                     sions would have locked.  This has no effect as a session
                     option; it must be set as a global option.

             message-attr attributes
                     Set status line message attributes, where attributes is
                     either default or a comma-delimited list of one or more
                     of: bright (or bold), dim, underscore, blink, reverse,
                     hidden, or italics.

             message-bg colour
                     Set status line message background colour, where colour
                     is one of: black, red, green, yellow, blue, magenta,
                     cyan, white, colour0 to colour255 from the 256-colour
                     palette, or default.

             message-fg colour
                     Set status line message foreground colour.

             message-limit number
                     Set the number of error or information messages to save
                     in the message log for each client.  The default is 20.

             mouse-select-pane [on | off]
                     If on, tmux captures the mouse and when a window is split
                     into multiple panes the mouse may be used to select the
                     current pane.  The mouse click is also passed through to
                     the application as normal.

             pane-border-fg colour

             pane-border-bg colour
                     Set the pane border colour for panes aside from the ac-
                     tive pane.

             pane-active-border-fg colour

             pane-active-border-bg colour
                     Set the pane border colour for the currently active pane.

             prefix keys
                     Set the keys accepted as a prefix key.  keys is a comma-
                     separated list of key names, each of which individually
                     behave as the prefix key.

             repeat-time time
                     Allow multiple commands to be entered without pressing
                     the prefix-key again in the specified time milliseconds
                     (the default is 500).  Whether a key repeats may be set
                     when it is bound using the -r flag to bind-key.  Repeat
                     is enabled for the default keys bound to the resize-pane
                     command.

             set-remain-on-exit [on | off]
                     Set the remain-on-exit window option for any windows
                     first created in this session.  When this option is true,
                     windows in which the running program has exited do not
                     close, instead remaining open but inactivate.  Use the
                     respawn-window command to reactivate such a window, or
                     the kill-window command to destroy it.

             set-titles [on | off]
                     Attempt to set the window title using the \e]2;...\007
                     xterm code if the terminal appears to be an xterm.  This
                     option is off by default.  Note that elinks will only at-
                     tempt to set the window title if the STY environment
                     variable is set.

             set-titles-string string
                     String used to set the window title if set-titles is on.
                     Character sequences are replaced as for the status-left
                     option.

             status [on | off]
                     Show or hide the status line.

             status-attr attributes
                     Set status line attributes.

             status-bg colour
                     Set status line background colour.

             status-fg colour
                     Set status line foreground colour.

             status-interval interval
                     Update the status bar every interval seconds.  By de-
                     fault, updates will occur every 15 seconds.  A setting of
                     zero disables redrawing at interval.

             status-justify [left | centre | right]
                     Set the position of the window list component of the sta-
                     tus line: left, centre or right justified.

             status-keys [vi | emacs]
                     Use vi or emacs-style key bindings in the status line,
                     for example at the command prompt.  Defaults to emacs.

             status-left string
                     Display string to the left of the status bar.  string
                     will be passed through strftime(3) before being used.  By
                     default, the session name is shown.  string may contain
                     any of the following special character sequences:

                           Character pair    Replaced with
                           #(shell-command)  First line of the command's
                                                              output
                           #[attributes]     Colour or attribute change
                           #H                Hostname of local host
                           #F                Current window flag
                           #I                Current window index
                           #P                Current pane index
                           #S                Session name
                           #T                Current window title
                           #W                Current window name
                           ##                A literal `#'

                     The #(shell-command) form executes `shell-command' and
                     inserts the first line of its output.  Note that shell
                     commands are only executed once at the interval specified
                     by the status-interval option: if the status line is re-
                     drawn in the meantime, the previous result is used.

                     #[attributes] allows a comma-separated list of attributes
                     to be specified, these may be `fg=colour' to set the
                     foreground colour, `bg=colour' to set the background
                     colour, the name of one of the attributes (listed under
                     the message-attr option) to turn an attribute on, or an
                     attribute prefixed with `no' to turn one off, for example
                     nobright.  Examples are:

                           #(sysctl vm.loadavg)
                           #[fg=yellow,bold]#(apm -l)%%#[default] [#S]

                     Where appropriate, special character sequences may be
                     prefixed with a number to specify the maximum length, for
                     example `#24T'.

                     By default, UTF-8 in string is not interpreted, to enable
                     UTF-8, use the status-utf8 option.

             status-left-attr attributes
                     Set the attribute of the left part of the status line.

             status-left-fg colour
                     Set the foreground colour of the left part of the status
                     line.

             status-left-bg colour
                     Set the background colour of the left part of the status
                     line.

             status-left-length length
                     Set the maximum length of the left component of the sta-
                     tus bar.  The default is 10.

             status-right string
                     Display string to the right of the status bar.  By de-
                     fault, the current window title in double quotes, the
                     date and the time are shown.  As with status-left, string
                     will be passed to strftime(3), character pairs are re-
                     placed, and UTF-8 is dependent on the status-utf8 option.

             status-right-attr attributes
                     Set the attribute of the right part of the status line.

             status-right-fg colour
                     Set the foreground colour of the right part of the status
                     line.

             status-right-bg colour
                     Set the background colour of the right part of the status
                     line.

             status-right-length length
                     Set the maximum length of the right component of the sta-
                     tus bar.  The default is 40.

             status-utf8 [on | off]
                     Instruct tmux to treat top-bit-set characters in the
                     status-left and status-right strings as UTF-8; notably,
                     this is important for wide characters.  This option de-
                     faults to off.

             terminal-overrides string
                     Contains a list of entries which override terminal de-
                     scriptions read using terminfo(5).  string is a comma-
                     separated list of items each a colon-separated string
                     made up of a terminal type pattern (matched using
                     fnmatch(3)) and a set of name=value entries.

                     For example, to set the `clear' terminfo(5) entry to
                     `\e[H\e[2J' for all terminal types and the `dch1' entry
                     to `\e[P' for the `rxvt' terminal type, the option could
                     be set to the string:

                           "*:clear=\e[H\e[2J,rxvt:dch1=\e[P"

                     The terminal entry value is passed through strunvis(3)
                     before interpretation.  The default value forcibly cor-
                     rects the `colors' entry for terminals which support 88
                     or 256 colours:

                           "*88col*:colors=88,*256col*:colors=256"

             update-environment variables
                     Set a space-separated string containing a list of envi-
                     ronment variables to be copied into the session environ-
                     ment when a new session is created or an existing session
                     is attached.  Any variables that do not exist in the
                     source environment are set to be removed from the session
                     environment (as if -r was given to the set-environment
                     command).  The default is "DISPLAY WINDOWID SSH_ASKPASS
                     SSH_AUTH_SOCK SSH_AGENT_PID SSH_CONNECTION".

             visual-activity [on | off]
                     If on, display a status line message when activity occurs
                     in a window for which the monitor-activity window option
                     is enabled.

             visual-bell [on | off]
                     If this option is on, a message is shown on a bell in-
                     stead of it being passed through to the terminal (which
                     normally makes a sound).  Also see the bell-action op-
                     tion.

             visual-content [on | off]
                     Like visual-activity, display a message when content is
                     present in a window for which the monitor-content window
                     option is enabled.

     set-window-option [-agu] [-t target-window] option value
                   (alias: setw)
             Set a window option.  The -a, -g and -u flags work similarly to
             the set-option command.

             Supported window options are:

             aggressive-resize [on | off]
                     Aggressively resize the chosen window.  This means that
                     tmux will resize the window to the size of the smallest
                     session for which it is the current window, rather than
                     the smallest session to which it is attached.  The window
                     may resize when the current window is changed on another
                     sessions; this option is good for full-screen programs
                     which support SIGWINCH and poor for interactive programs
                     such as shells.

             automatic-rename [on | off]
                     Control automatic window renaming.  When this setting is
                     enabled, tmux will attempt - on supported platforms - to
                     rename the window to reflect the command currently run-
                     ning in it.  This flag is automatically disabled for an
                     individual window when a name is specified at creation
                     with new-window or new-session, or later with rename-
                     window.  It may be switched off globally with:

                           set-window-option -g automatic-rename off

             clock-mode-colour colour
                     Set clock colour.

             clock-mode-style [12 | 24]
                     Set clock hour format.

             force-height height
             force-width width
                     Prevent tmux from resizing a window to greater than width
                     or height.  A value of zero restores the default unlimit-
                     ed setting.

             main-pane-width width
             main-pane-height height
                     Set the width or height of the main (left or top) pane in
                     the main-horizontal or main-vertical layouts.

             mode-attr attributes
                     Set window modes attributes.

             mode-bg colour
                     Set window modes background colour.

             mode-fg colour
                     Set window modes foreground colour.

             mode-keys [vi | emacs]
                     Use vi or emacs-style key bindings in copy and choice
                     modes.  Key bindings default to emacs.

             mode-mouse [on | off]
                     Mouse state in modes.  If on, tmux will respond to mouse
                     clicks by moving the cursor in copy mode or selecting an
                     option in choice mode.

             monitor-activity [on | off]
                     Monitor for activity in the window.  Windows with activi-
                     ty are highlighted in the status line.

             monitor-content match-string
                     Monitor content in the window.  When fnmatch(3) pattern
                     match-string appears in the window, it is highlighted in
                     the status line.

             remain-on-exit [on | off]
                     A window with this flag set is not destroyed when the
                     program running in it exits.  The window may be reacti-
                     vated with the respawn-window command.

             synchronize-panes [on | off]
                     Duplicate input to any pane to all other panes in the
                     same window, except for panes that are not in output
                     mode.

             alternate-screen [on | off]
                     This option configures whether programs running inside
                     tmux may use the terminal alternate screen feature, which
                     allows the smcup and rmcup terminfo(5) capabilities to be
                     issued to preserve the existing window content on start
                     and restore it on exit.

             utf8 [on | off]
                     Instructs tmux to expect UTF-8 sequences to appear in
                     this window.

             window-status-attr attributes
                     Set status line attributes for a single window.

             window-status-bg colour
                     Set status line background colour for a single window.

             window-status-fg colour
                     Set status line foreground colour for a single window.

             window-status-format string
                     Set the format in which the window is displayed in the
                     status line window list.  See the status-left option for
                     details of special character sequences available.  The
                     default is `#I:#W#F'.

             window-status-current-attr attributes
                     Set status line attributes for the currently active win-
                     dow.

             window-status-current-bg colour
                     Set status line background colour for the currently ac-
                     tive window.

             window-status-current-fg colour
                     Set status line foreground colour for the currently ac-
                     tive window.

             window-status-current-format string
                     Like window-status-format, but is the format used when
                     the window is the current window.

             word-separators string
                     Sets the window's conception of what characters are con-
                     sidered word separators, for the purposes of the next and
                     previous word commands in copy mode.  The default is
                     ` -_@'.

             xterm-keys [on | off]
                     If this option is set, tmux will generate xterm(1)-style
                     function key sequences; these have a number included to
                     indicate modifiers such as Shift, Alt or Ctrl.  The de-
                     fault is off.

     show-options [-gsw] [-t target-session | target-window]
                   (alias: show)
             Show the window options with -w (equivalent to show-window-
             options), the server options with -s, otherwise the session op-
             tions for target session.  Global session or window options are
             listed if -g is used.

     show-window-options [-g] [-t target-window]
                   (alias: showw)
             List the window options for target-window, or the global window
             options if -g is used.

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 with
     the session environment overriding any variable present in both.  This 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 reat-
     tached.  tmux also initialises the TMUX variable with some internal in-
     formation to allow commands to be executed from inside, and the TERM
     variable with the correct terminal setting of `screen'.

     Commands to alter and view the environment are:

     set-environment [-gru] [-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.  The -u flag unsets a
             variable.  -r indicates the variable is to be removed from the
             environment before starting a new process.

     show-environment [-g] [-t target-session]
                   (alias: showenv)
             Display the environment for target-session or the global environ-
             ment with -g.  Variables removed from the environment are pre-
             fixed with `-'.

STATUS LINE
     tmux includes an optional status line which is displayed in the bottom
     line of each terminal.  By default, the status line is enabled (it may be
     disabled with the status session option) and contains, from left-to-
     right: the name of the current session in square brackets; the window
     list; the current window title in double quotes; and the time and date.

     The status line is made of three parts: configurable left and right sec-
     tions (which may contain dynamic content such as the time or output from
     a shell command, see the status-left, status-left-length, status-right,
     and status-right-length options below), and a central window list.  By
     default, the window list shows the index, name and (if any) flag of the
     windows present in the current session in ascending numerical order.  It
     may be customised with the window-status-format and window-status-
     current-format options.  The flag is one of the following symbols append-
     ed to the window name:

           Symbol    Meaning
           *         Denotes the current window.
           -         Marks the last window (previously selected).
           #         Window is monitored and activity has been detected.
           !         A bell has occurred in the window.
           +         Window is monitored for content and it has appeared.

     The # symbol relates to the monitor-activity and + to the monitor-content
     window options.  The window name is printed in inverted colours if an
     alert (bell, activity or content) is present.

     The colour and attributes of the status line may be configured, the en-
     tire status line using the status-attr, status-fg and status-bg session
     options and individual windows using the window-status-attr, window-
     status-fg and window-status-bg window options.

     The status line is automatically refreshed at interval if it has changed,
     the interval may be controlled with the status-interval session option.

     Commands related to the status line are as follows:

     command-prompt [-p prompts] [-t target-client] [template]
             Open the command prompt in a client.  This may be used from in-
             side tmux to execute commands interactively.  If template is
             specified, it is used as the command.  If -p is given, prompts is
             a comma-separated list of prompts which are displayed in order;
             otherwise a single prompt is displayed, constructed from template
             if it is present, or `:' if not.  Before the command is executed,
             the first occurrence of the string `%%' and all occurrences of
             `%1' are replaced by the response to the first prompt, the second
             `%%' and all `%2' are replaced with the response to the second
             prompt, and so on for further prompts.  Up to nine prompt re-
             sponses may be replaced (`%1' to `%9').

     confirm-before [-t target-client] command
                   (alias: confirm)
             Ask for confirmation before executing command.  This command
             works only from inside tmux.

     display-message [-p] [-t target-client] [message]
                   (alias: display)
             Display a message.  If -p is given, the output is printed to std-
             out, otherwise it is displayed in the target-client status line.
             The format of message is as for status-left, with the exception
             that #() are not handled.

     select-prompt [-t target-client]
             Open a prompt inside target-client allowing a window index to be
             entered interactively.

BUFFERS
     tmux maintains a stack of paste buffers for each session.  Up to the val-
     ue of the buffer-limit option are kept; when a new buffer is added, the
     buffer at the bottom of the stack is removed.  Buffers may be added using
     copy-mode or the set-buffer command, and pasted into a window using the
     paste-buffer command.

     A configurable history buffer is also maintained for each window.  By de-
     fault, up to 2000 lines are kept; this can be altered with the history-
     limit option (see the set-option command above).

     The buffer commands are as follows:

     clear-history [-t target-pane]
                   (alias: clearhist)
             Remove and free the history for the specified pane.

     copy-buffer [-a src-index] [-b dst-index] [-s src-session] [-t
             dst-session]
                   (alias: copyb)
             Copy a session paste buffer to another session.  If no sessions
             are specified, the current one is used instead.

     delete-buffer [-b buffer-index] [-t target-session]
                   (alias: deleteb)
             Delete the buffer at buffer-index, or the top buffer if not spec-
             ified.

     list-buffers [-t target-session]
                   (alias: lsb)
             List the buffers in the given session.

     load-buffer [-b buffer-index] [-t target-session] path
                   (alias: loadb)
             Load the contents of the specified paste buffer from path.

     paste-buffer [-dr] [-b buffer-index] [-t target-window]
                   (alias: pasteb)
             Insert the contents of a paste buffer into the current window.
             With -d, also delete the paste buffer from the stack.  When out-
             put, any linefeed (LF) characters in the paste buffer are re-
             placed with carriage returns (CR).  This translation may be dis-
             abled with the -r flag.

     save-buffer [-a] [-b buffer-index] [-t target-session] path
                   (alias: saveb)
             Save the contents of the specified paste buffer to path.  The -a
             option appends to rather than overwriting the file.

     set-buffer [-b buffer-index] [-t target-session] data
                   (alias: setb)
             Set the contents of the specified buffer to data.

     show-buffer [-b buffer-index] [-t target-session]
                   (alias: showb)
             Display the contents of the specified buffer.

MISCELLANEOUS
     Miscellaneous commands are as follows:

     clock-mode [-t target-pane]
             Display a large clock.

     if-shell shell-command command
                   (alias: if)
             Execute command if shell-command returns success.

     lock-server
                   (alias: lock)
             Lock each client individually by running the command specified by
             the lock-command option.

     run-shell shell-command
                   (alias: run)
             Execute shell-command in the background without creating a win-
             dow.  After it finishes, any output to stdout is displayed in
             output mode.  If the command doesn't return success, the exit
             status is also displayed.

     server-info
                   (alias: info)
             Show server information and terminal details.

FILES
     ~/.tmux.conf       Default tmux configuration file.
     /etc/tmux.conf     System-wide configuration file.

EXAMPLES
     To create a new tmux session running vi(1):

           $ tmux new-session vi

     Most commands have a shorter form, known as an alias.  For new-session,
     this is new:

           $ tmux new vi

     Alternatively, the shortest unambiguous form of a command is accepted.
     If there are several options, they are listed:

           $ tmux n
           ambiguous command: n, could be: new-session, new-window, next-window

     Within an active session, a new window may be created by typing `C-b c'
     (Ctrl followed by the `b' key followed by the `c' key).

     Windows may be navigated with: `C-b 0' (to select window 0), `C-b 1' (to
     select window 1), and so on; `C-b n' to select the next window; and `C-b
     p' to select the previous window.

     A session may be detached using `C-b d' (or by an external event such as
     ssh(1) disconnection) and reattached with:

           $ tmux attach-session

     Typing `C-b ?' lists the current key bindings in the current window; up
     and down may be used to navigate the list or `q' to exit from it.

     Commands to be run when the tmux server is started may be placed in the
     ~/.tmux.conf configuration file.  Common examples include:

     Changing the default prefix key:

           set-option -g prefix C-a
           unbind-key C-b
           bind-key C-a send-prefix

     Turning the status line off, or changing its colour:

           set-option -g status off
           set-option -g status-bg blue

     Setting other options, such as the default command, or locking after 30
     minutes of inactivity:

           set-option -g default-command "exec /bin/ksh"
           set-option -g lock-after-time 1800

     Creating new key bindings:

           bind-key b set-option status
           bind-key / command-prompt "split-window 'exec man %%'"
           bind-key S command-prompt "new-window -n %1 'ssh %1'"

SEE ALSO
     pty(4)

AUTHORS
     Nicholas Marriott <nicm@users.sourceforge.net>

OpenBSD 4.7                      March 2, 2010                              23
