psmux Command and Flag Reference

This is the reference for the commands psmux itself accepts and the flags psmux itself parses. Every entry was read out of the psmux Rust sources, not out of the upstream tmux manual, so a flag listed here is a flag psmux actually looks at. Where tmux has a flag and psmux does not parse it, the flag is either absent from this page or listed under "Accepted but ignored".

psmux list-commands is the live authority. If this page and list-commands disagree, list-commands wins and this page is stale.

How to read this page

Layers. psmux matches command names in four separate places, and they do not all accept the same set. A command is usable only on the layers listed for it.

Layer	What reaches it
CLI	psmux <command> typed in a shell
SRV	key bindings, and anything the CLI forwards over the socket
CFG	config file lines, hooks, run-shell, if-shell, bind-key actions
CTL	control mode clients (psmux -C / psmux -CC)

The flags column uses getopt style notation. A bare letter is a boolean, a letter followed by : takes a value. -t: therefore means -t <target>.

-t is global at the CLI. psmux scans the whole command line for -t <target> before the command name is even dispatched, so psmux -t work:1 kill-pane and psmux kill-pane -t work:1 both work even for commands whose own parser ignores -t.

Combined short flags are expanded for new-session (-As main is -A -s main), for set-option and show-options (-ga, -gu, -gq), for set-hook (-ga, -ug) and for the config file forms of if-shell (-bF, -Fb). Elsewhere flags must be given separately.

Complete command table

Command	Aliases	Flags psmux parses	Layers
attach-session	attach, a, at	t:	CLI, SRV, CFG
bind-key	bind	nrT:	CLI, SRV, CFG, CTL
break-pane	breakp	dt:	CLI, SRV, CFG, CTL
capture-pane	capturep	eJpb:E:S:t:	CLI, SRV, CFG, CTL
choose-buffer	chooseb	none	CLI, SRV, CFG
choose-client	(none)	none	CLI, SRV, CFG
choose-session	(none)	none	CLI, SRV, CFG
choose-tree	(none)	none	CLI, SRV, CFG
choose-window	(none)	none	CLI, SRV, CFG
clear-history	clearhist	Ht:	CLI, SRV, CFG
clear-prompt-history	clearphist	none	SRV
clock-mode	(none)	none	CLI, SRV, CFG
command-prompt	(none)	NWI:p:T:t:	CLI, SRV, CFG
confirm-before	confirm	p:	CLI, SRV, CFG
copy-mode	(none)	deHqut:	CLI, SRV, CFG, CTL
customize-mode	(none)	none	CLI, SRV, CFG
delete-buffer	deleteb	b:	CLI, SRV, CFG
detach-client	detach	aPE:s:t:	CLI, SRV, CFG, CTL
display-menu	menu	T:x:y:	CLI, SRV, CFG
display-message	display	pFd:I:t:	CLI, SRV, CFG, CTL
display-panes	displayp	none	CLI, SRV, CFG
display-popup	popup	EKc:d:h:w:	CLI, SRV, CFG
dump-layout	(none)	none	SRV
dump-state	dump	none	CLI, SRV, CTL
find-window	findw	none that take effect	CLI, SRV, CFG
has-session	has	t:	CLI, SRV, CFG, CTL
if-shell	if	bFt:	CLI, SRV, CFG
join-pane	joinp	dhvs:t:	CLI, SRV, CFG
kill-pane	killp	t:	CLI, SRV, CFG, CTL
kill-server	(none)	none	CLI, SRV, CFG, CTL
kill-session	kill-ses	t:	CLI, SRV, CFG
kill-window	killw	at:	CLI, SRV, CFG, CTL
last-pane	lastp	none	CLI, SRV, CFG, CTL
last-window	last	none	CLI, SRV, CFG, CTL
link-window	linkw	s:t:	CLI, SRV, CFG
list-buffers	lsb	F:t:	CLI, SRV, CFG, CTL
list-clients	lsc	F: (SRV and CTL only)	CLI, SRV, CFG, CTL
list-commands	lscm	none	CLI, SRV, CFG, CTL
list-keys	lsk	T:t:	CLI, SRV, CFG, CTL
list-panes	lsp	asF:t:	CLI, SRV, CFG, CTL
list-sessions	ls	F:f:	CLI, SRV, CFG, CTL
list-tree	(none)	none	SRV
list-windows	lsw	aJF:t:	CLI, SRV, CFG, CTL
load-buffer	loadb	wb:	CLI, SRV, CFG
lock-client	lockc	none	CLI, SRV, CFG
lock-server	lock	none	CLI, SRV, CFG
lock-session	locks	none	CLI, SRV, CFG
move-pane	movep	dhvs:t:	CLI, SRV, CFG
move-window	movew	abrdks:t:	CLI, SRV, CFG
new-pane	newp	dPEB:T:c:x:y:X:Y:	CLI, SRV, CTL
new-session	new	AdPc:e:F:f:n:s:t:x:y:	CLI, SRV, CFG
new-window	neww	dPEc:e:F:n:T:t:	CLI, SRV, CFG, CTL
next-layout	nextl (not at the CLI)	none	CLI, SRV, CFG, CTL
next-window	next	none	CLI, SRV, CFG, CTL
paste-buffer	pasteb	dpb:t:	CLI, SRV, CFG
pipe-pane	pipep	IOot:	CLI, SRV, CFG
previous-layout	prevl (not at the CLI)	none	CLI, SRV, CFG
previous-window	prev	none	CLI, SRV, CFG, CTL
refresh-client	refresh	SlC:t: at the CLI, plus A:B:f: in control mode	CLI, SRV, CFG, CTL
rename-session	rename	none, takes the new name as a positional argument	CLI, SRV, CFG, CTL
rename-window	renamew	none, takes the new name as a positional argument	CLI, SRV, CFG, CTL
resize-pane	resizep	UDLRZx:y:t:	CLI, SRV, CFG, CTL
resize-window	resizew	aADLRUx:y:t:	CLI, SRV, CFG, CTL
respawn-pane	respawnp, resp	kc:t: plus -- <command>	CLI, SRV, CFG, CTL
respawn-window	respawnw	none	CLI, SRV, CFG
rotate-window	rotatew	UDt:	CLI, SRV, CFG, CTL
run-command	runcmd	none, takes the command line as positional arguments	SRV, CTL
run-shell	run	b	CLI, SRV, CFG
save-buffer	saveb	ab:	CLI, SRV, CFG
select-layout	selectl	npoEt: plus a positional layout name	CLI, SRV, CFG, CTL
select-pane	selectp	UDLRlZmMedP:T:t:	CLI, SRV, CFG, CTL
select-window	selectw	lnpt:	CLI, SRV, CFG, CTL
send-keys	send, send-key	lRXN:t:	CLI, SRV, CFG, CTL
send-paste	(none)	t: plus a positional payload	CLI, SRV
send-prefix	(none)	none	CLI, SRV, CFG
send-text	(none)	none, takes the text as positional arguments	SRV
server-info	info	none	CLI, SRV, CFG, CTL
set-buffer	setb	wb:	CLI, SRV, CFG
set-environment	setenv	grhut:	CLI, SRV, CFG, CTL
set-hook	(none)	gua	CLI, SRV, CFG, CTL
set-option	set	guaqowt:p:	CLI, SRV, CFG, CTL
set-pane-title	(none)	none, takes the title as positional arguments	SRV
set-window-option	setw	guaqowt:p:	CLI, SRV, CFG, CTL
show-buffer	showb	b:	CLI, SRV, CFG, CTL
show-environment	showenv	gsht:	CLI, SRV, CFG, CTL
show-hooks	(none)	g	CLI, SRV, CFG, CTL
show-messages	showmsgs	none	CLI, SRV, CFG
show-options	show	Aswvqt:	CLI, SRV, CFG, CTL
show-prompt-history	showphist	none	SRV
show-window-options	showw	Aswvqt:	CLI, SRV, CFG, CTL
source-file	source	qnv	CLI, SRV, CFG, CTL
split-window	splitw, split-pane, splitp	hvdPc:e:F:l:p:T:t:	CLI, SRV, CFG, CTL
start-server	start, warmup	none	CLI, SRV, CFG
suspend-client	suspendc	none	CLI, SRV, CFG
swap-pane	swapp	UDds:t:	CLI, SRV, CFG, CTL
swap-window	swapw	ds:t:	CLI, SRV, CFG
switch-client	switchc	lnprc:t: plus T: on SRV	CLI, SRV, CFG
toggle-sync	(none)	none	SRV, CFG
unbind-key	unbind	anT:t:	CLI, SRV, CFG, CTL
unlink-window	unlinkw	none, acts on the active window	CLI, SRV, CFG, CTL
wait-for	wait	LSU	CLI, SRV, CFG
zoom-pane	(none)	none	CLI, SRV, CFG, CTL

102 command names. warmup, resp, a and at are CLI only aliases. nextl and prevl are recognised on the server, config and control layers but not by the CLI front end, so use the full name when typing in a shell.

Commands deliberately not listed

The server also matches a set of internal wire commands that the client sends on your behalf and that are not meant to be typed: the overlay and chooser wire (popup-input, menu-select, customize-navigate, confirm-respond and friends), the cross session pane transfer wire (pane-forward-extract, pane-forward-inject and friends), the layout drag wire (split-sizes, split-resize-done), claim-session, session-info, client-attach, client-detach, server-access, window-layout, window-dump, and the copy mode key wire (copy-enter, copy-move, copy-anchor, copy-yank, rectangle-toggle, copy-mode-page-up, delete-buffer-at, paste-buffer-at).

Five mouse wire commands are an exception and are genuinely usable for scripting: mouse-down, mouse-drag, mouse-up, mouse-down-right and mouse-up-right are accepted at the CLI as well as on the socket.

select-window-index appears in the default prefix bindings but is a client side pseudo command. psmux select-window-index fails with "unknown command" and it cannot be used from a config line, a hook or run-shell.

Flag details by command

Session commands

new-session (new)

• Boolean: -A (attach if the session already exists), -d (detached), -P (print the new session info)
• Value: -s (session name), -n (first window name), -c (start directory), -x (initial width), -y (initial height), -e (environment KEY=VALUE, repeatable), -F (format), -f (value consumed and discarded), -t (session group target)
• -- ends option parsing. Everything after it is the raw command to run instead of a shell.
• Accepted but ignored, for tmux script compatibility: -D, -E, -X
• Not accepted: -g. Session groups are set with set -g session-group <name>, not with a new-session flag.
• Combined short flags are expanded, so -As main means -A -s main and -dP means -d -P.

attach-session (attach, a, at)

• Value: -t (target session)
• A bare positional argument is also accepted as the session name, so psmux attach work works.
• Not accepted: -d, -D, -E, -r, -c, -f, -x, -y

has-session (has)

• Value: -t (target session). A leading = is stripped, matching tmux exact match semantics.

kill-session (kill-ses)

• Value: -t (target session)
• Not accepted: -a, -C

rename-session (rename)

• No flags. The first positional argument is the new name.

list-sessions (ls)

• Value: -F (format, also accepted glued as -F<format>), -f (filter)
• Any other -x token is rejected with a usage error and a non-zero exit, so scripts see the failure.

switch-client (switchc)

• Boolean: -l (last), -n (next), -p (previous), -r (toggle read only)
• Value: -c (client), -t (target, a full session:window.pane target is honored)
• Server layer only: -T (switch the active key table)
• Not accepted: -E, -F, -O, -Z

detach-client (detach)

• Boolean: -a (detach all other clients), -P (kill the parent process)
• Value: -t (target client), -s (target session), -E (command that replaces the shell on detach)

suspend-client (suspendc)

• No flags. This is a no-op on Windows, which has no SIGTSTP.

lock-server (lock), lock-session (locks), lock-client (lockc)

• No flags. All three are no-ops on Windows, which has no terminal locking concept.

kill-server

• No flags.
• Note: bare kill-server stops every socket and session (the default plus all -L namespaces), unlike tmux which only kills the current socket. Use -L <name> kill-server to scope it to one namespace. See compatibility.md.

start-server (start, warmup)

• No flags. Pre-spawns a warm server so the next new-session is instant.

server-info (info)

• No flags.

list-clients (lsc)

• Value: -F (format), honored on the server and control mode layers. The CLI front end forwards a bare list-clients, so psmux list-clients -F ... silently drops the format.

choose-client

• No flags. psmux has a single client model, so this returns the current client info.

refresh-client (refresh)

• Boolean: -S (status line only), -l (request the clipboard)
• Value: -C (client size), -t (target client)
• Control mode adds: -A '%<pane>:continue' (resume a paused pane), -B 'name:target:format' (add a subscription, -B 'name:' removes it), -f pause-after=N and -f no-pause (flow control)
• The control mode -C argument is comma separated (-C 120,30), which is the form iTerm2 sends.
• Not accepted: -c, -D, -L, -R, -U, -r, -F

Window commands

new-window (neww)

• Boolean: -d (do not switch to the new window), -P (print the new window info), -E (empty pane, no shell)
• Value: -n (window name), -c (start directory), -T (pane title), -e (environment KEY=VALUE), -F (format, also accepted glued as -F<format>), -t (target, value consumed)
• Accepted but ignored: -a, -D, -k, -S
• Not accepted: -b

kill-window (killw)

• Boolean: -a (kill all windows but the current one)
• Value: -t (target window)

unlink-window (unlinkw)

• No flags. Acts on the active window.
• Not accepted: -k

rename-window (renamew)

• No flags. The first positional argument is the new name.

select-window (selectw)

• Boolean: -l (last), -n (next), -p (previous)
• Value: -t (target window, session:@id form is honored)
• Not accepted: -T

next-window (next), previous-window (prev), last-window (last)

• No flags.

move-window (movew)

• Boolean: -a (after), -b (before), -r (renumber), -d (do not switch), -k (kill the target if it exists)
• Value: -s (source window), -t (destination window). A bare numeric -t is treated as a window index, not a session.

link-window (linkw)

• Value: -s (source window index), -t (destination window index)
• Not accepted: -a, -b, -d, -k

swap-window (swapw)

• Boolean: -d (do not switch)
• Value: -s (source window), -t (destination window). A bare numeric -t is treated as a window index.

rotate-window (rotatew)

• Boolean: -U (rotate up), -D (rotate down)
• Value: -t (target window)
• Not accepted: -Z

resize-window (resizew)

• Boolean: -A (largest client), -a (smallest client), -L, -R, -U, -D
• Value: -x (width), -y (height), -t (target window)
• Positional: optional positive adjustment for -L, -R, -U, or -D (default 1)
• The target window enters manual sizing; later client viewport changes do not overwrite it.

find-window (findw)

• The first positional argument is the search pattern. That is the only thing that has an effect.
• Accepted but ignored: -C, -N, -T, -i, -r, -Z, -t

respawn-window (respawnw)

• No flags. Respawns the active pane of the window.

list-windows (lsw)

• Boolean: -a (all sessions), -J (JSON output, a psmux extension)
• Value: -F (format), -t (target session)

Pane commands

split-window (splitw, split-pane, splitp)

• Boolean: -h (horizontal), -v (vertical), -d (do not switch), -P (print the new pane info)
• Value: -p (percentage size), -l (size in cells or a percentage), -c (start directory), -T (pane title), -F (format), -e (environment KEY=VALUE), -t (target, value consumed)
• Accepted but ignored: -b, -f, -I, -Z

new-pane (newp) A psmux extension that creates a pane floating above the tiled layout.

• Boolean: -d (detached), -P (print the new pane id), -E (empty, no shell)
• Value: -B (border style), -T (title), -c (start directory), -x (width), -y (height), -X (column position), -Y (row position)

select-pane (selectp)

• Boolean: -U, -D, -L, -R (directional), -l (last pane), -Z (keep the zoom while navigating), -m (mark), -M (unmark), -e (enable input), -d (disable input)
• Value: -T (set and lock the pane title), -P (pane style), -t (target pane)
• -t also accepts positional targets: {top}, {bottom}, {left}, {right}, {top-left}, {top-right}, {bottom-left}, {bottom-right}
• Not accepted: -g

last-pane (lastp)

• No flags.

kill-pane (killp)

• Value: -t (target pane, via the global -t handler)
• Not accepted: -a

resize-pane (resizep)

• Boolean: -U, -D, -L, -R (directional), -Z (toggle zoom)
• Value: -x (absolute width in cells), -y (absolute height in cells), -t (target pane)
• Not accepted: -M, -T

zoom-pane

• No flags. A psmux extension with no tmux equivalent. resize-pane -Z does the same thing.

swap-pane (swapp)

• Boolean: -U (swap up), -D (swap down), -d (do not move the active pane)
• Value: -s (source pane), -t (destination pane)
• Not accepted: -Z

join-pane (joinp) and move-pane (movep)

• Boolean: -h (horizontal), -v (vertical, the default), -d (do not switch)
• Value: -s (source pane), -t (destination pane)
• A -s <other-session>:... source moves a live pane between independent servers.
• Not accepted: -b, -f, -p, -l

break-pane (breakp)

• Boolean: -d (do not switch to the new window)
• Value: -t (target)
• Not accepted: -a, -b, -P, -F, -n, -s

respawn-pane (respawnp, resp)

• Boolean: -k (kill the existing process first)
• Value: -c (start directory), -t (target pane)
• -- <command> is honored and replaces the pane command.
• Not accepted: -e

capture-pane (capturep)

• Boolean: -p (print to stdout), -e (include escape sequences), -J (join wrapped lines)
• Value: -S (start line), -E (end line), -b (buffer name), -t (target pane)
• Not accepted: -a, -C, -M, -N, -P, -q, -T

clear-history (clearhist)

• Boolean: -H (also clear the alternate screen)
• Value: -t (target pane)

list-panes (lsp)

• Boolean: -a (all sessions), -s (session scope)
• Value: -F (format), -t (target)

display-panes (displayp)

• No flags. Shows the pane number overlay, then a digit key selects a pane.

pipe-pane (pipep)

• Boolean: -I (pipe input), -O (pipe output), -o (toggle)
• Value: -t (target pane)

set-pane-title

• No flags. A psmux extension. The positional arguments are joined into the title.

toggle-sync

• No flags. A psmux extension that toggles synchronize-panes for the active window.

Layout commands

select-layout (selectl)

• Boolean: -n (next layout), -p (previous layout)
• Value: -t (target, value consumed)
• Accepted but ignored: -o, -E
• The first positional argument is a layout name: even-horizontal (alias even-h), even-vertical, main-horizontal (alias main-h), main-vertical (alias main-v), tiled.

next-layout, previous-layout

• No flags. nextl and prevl work on the server, config and control layers but not at the CLI.

Copy and paste commands

copy-mode

• Boolean: -u (scroll up one page on entry), -d (scroll down), -e (exit at the bottom), -H (hide the position indicator), -q (quit copy mode)
• Value: -t (target pane)
• Not accepted: -M, -S, -s
• In control mode copy-mode is a success returning no-op, because iTerm2 implements copy mode locally on captured content.

paste-buffer (pasteb)

• Boolean: -d (delete the buffer after pasting), -p (use bracketed paste)
• Value: -b (buffer name), -t (target pane)
• Not accepted: -r, -s
• When the buffer stack is empty, psmux falls back to the Windows clipboard.

set-buffer (setb)

• Boolean: -w (also write to the Windows clipboard)
• Value: -b (buffer name)
• Not accepted: -a, -n, -t

delete-buffer (deleteb) and show-buffer (showb)

• Value: -b (buffer name)

save-buffer (saveb)

• Boolean: -a (append)
• Value: -b (buffer name). The first positional argument is the path.

load-buffer (loadb)

• Boolean: -w (propagate to the clipboard)
• Value: -b (buffer name). The first positional argument is the path.

list-buffers (lsb)

• Value: -F (format), -t (value consumed and discarded)

choose-buffer (chooseb)

• No flags. Opens the interactive buffer chooser.

Key binding commands

bind-key (bind)

• Boolean: -n (shorthand for -T root), -r (repeatable)
• Value: -T (key table)
• Not accepted: -N (note)

unbind-key (unbind)

• Boolean: -a (unbind everything, also matched inside a combined token), -n (root table)
• Value: -T (key table), -t (target, value consumed)
• Not accepted: -q

list-keys (lsk)

• Value: -T (key table), -t (value consumed and discarded)
• Not accepted: -1, -a, -N, -P

send-keys (send, send-key)

• Boolean: -l (literal), -R (reset the terminal state), -X (run a copy mode command)
• Value: -N (repeat count, value consumed), -t (target pane)
• Not accepted: -c, -F, -H, -K, -M
• Named key tokens accepted as arguments: ENTER, TAB, BTAB / BACKTAB, ESCAPE / ESC, SPACE, BSPACE / BACKSPACE, UP, DOWN, LEFT, RIGHT, HOME, END, PAGEUP / PPAGE, PAGEDOWN / NPAGE, DELETE / DC, INSERT / IC

send-prefix

• No flags.
• Not accepted: -2, -t

send-text, send-paste

• psmux extensions. send-text takes the raw text as positional arguments and does no key name parsing. send-paste wraps the payload in a bracketed paste sequence and also accepts -t at the CLI.

Configuration commands

set-option (set) and set-window-option (setw)

• Boolean: -g (global, accepted, psmux has one scope so this is effectively a selector no-op), -u (unset), -U (unset alias of -u, tmux parity, #553), -a (append to the current value), -q (quiet), -o (only set if currently unset), -w (window scope, does not consume the next argument)
• Value: -t (target, value consumed), -p (pane, value consumed)
• Flags are also matched inside combined tokens such as -ga, -gu and -gq.
• A @name argument is never treated as a flag.
• Not accepted: -F, -s — and since #553 any flag outside the accepted set is rejected with unknown flag -X at exit 1 instead of being silently dropped while the write lands.

show-options (show) and show-window-options (showw)

• Boolean: -A (include inherited), -s (server scope), -w (window scope), -v (value only), -q (quiet)
• Value: -t (window selector)
• Combined tokens are handled the same way as for set-option.
• Not accepted: -g as a distinct behavior (it is absorbed but tolerated), -H, -p — since #553 flags outside -A -g -q -s -v -w (plus -t <target>) are rejected with unknown flag -X at exit 1.

set-hook and show-hooks

• Boolean: -u (unset, also as -gu or -ug), -a (append, also as -ga or -ag), -g (global, accepted and absorbed)
• Not accepted: -p, -R, -w, -t
• set-hook accepts any hook name with no validation, so a typo silently never fires.

set-environment (setenv)

• Boolean: -g (global), -r (remove from the environment), -u (unset), -h (hidden)
• Value: -t (target session)
• Not accepted: -F

show-environment (showenv)

• Boolean: -g (global), -s (shell format), -h (hidden)
• Value: -t (target session)

source-file (source)

• Boolean: -q (quiet), -n (parse only, do not execute), -v (verbose)
• Not accepted: -F, -t

list-commands (lscm)

• No flags.
• Not accepted: -F

Display and overlay commands

display-message (display)

• Boolean: -p (print to stdout), -F (format mode)
• Value: -d (display duration in ms), -I (value consumed), -t (target)
• -- ends option parsing.
• Not accepted: -a, -C, -c, -l, -N, -v

display-menu (menu)

• Value: -x (column), -y (row), -T (title)
• Menu items follow as <label> <key> <command> triples.

display-popup (popup)

• Boolean: -E (close when the command exits, which is already the default), -K (keep the popup open after the command exits)
• Value: -w (width, cells or a percentage), -h (height), -d or -c (start directory)

confirm-before (confirm)

• Value: -p (prompt text)
• Everything that is not the prompt and does not begin with - becomes the command to confirm.
• Not accepted: -b, -c, -y, -t

command-prompt

• Boolean: -N (numeric input only), -W (word input only)
• Value: -I (initial value), -p (prompt list), -T (prompt type), -t (target)
• Not accepted: -1, -b, -e, -F, -i, -k, -l

choose-tree, choose-window, choose-session, choose-client, choose-buffer, customize-mode, clock-mode

• No flags. These open client side overlays. While an overlay is open its keys are handled before any key table, so a bound key does not reach the tables until the overlay closes.

show-messages (showmsgs)

• No flags.

clear-prompt-history (clearphist) and show-prompt-history (showphist)

• No flags. Server layer only, so reach them from a key binding or a raw socket connection rather than from psmux <command>.

Shell and flow control commands

run-shell (run)

• Boolean: -b (background)
• Everything else, including tokens that look like flags, is treated as part of the shell command. -C, -d, -s, -c and -t are not parsed, so passing them sends them straight to the shell.

if-shell (if)

• Boolean: -b (background), -F (evaluate the condition as a format string instead of running a shell)
• Value: -t (value consumed and discarded)
• Positional arguments: the condition, the command to run when it succeeds, and optionally the command to run when it fails.
• The config file parser also accepts the glued combined forms -bF and -Fb.

wait-for (wait)

• Boolean: -L (lock), -S (signal), -U (unlock)
• The first positional argument is the channel name.

run-command (runcmd)

• No flags. Runs the given command line through the config file command layer and returns its output, with a 15 second timeout. Available on the server and control mode layers.

dump-state (dump), dump-layout, list-tree

• No flags. dump-state returns the whole live server state as JSON and is available at the CLI and in control mode. dump-layout and list-tree are server layer only.

Global flags, before the command name

These are parsed before psmux looks at the command name.

Flag	Meaning
-L <name>	Socket namespace. Sessions in a namespace are stored as <name>__<session>.
-f <file>	Config file to load, exported as PSMUX_CONFIG_FILE.
-C	Control mode with command echo.
-CC	Control mode without command echo.
-t <target>	Target session, session:window or session:window.pane for the command that follows.
-S <path>	Socket path, accepted and its value consumed.
-h, --help	Usage.
-V, -v, --version	Version.

Glued short flags of the form -x=VALUE are normalized to -x VALUE before parsing.

User defined command aliases

set -g command-alias '<alias>=<expansion>' defines your own command names. There is one asymmetry worth knowing: aliases resolve from key bindings and config lines, and are consulted by the config file unknown command warning, but the CLI front end does not resolve them. psmux <alias> fails with "unknown command" while the same alias in a key binding or a config line works.