# libtmux.data/panes

- **Module:** libtmux.data
- **Package:** io.github.libtmux:libtmux-clojure
- **Language:** Clojure
- **Kind:** function
- **Source:** https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/libtmux-clojure/src/main/clojure/libtmux/data.clj#L134
- **Public owner:** libtmux.data
- **Page:** https://libtmux.org/en/clojure/latest/reference/libtmux-data-panes/

```
(panes value)
```

Returns captured pane occurrences in a snapshot, session, or window.

Use [[libtmux.core/panes!]] for a new acquisition; [[active-pane]] selects locally.

## Examples

Traverse root, session, window and pane observations. Use JDK 25 or newer, the Clojure CLI, Git and tmux on Linux or macOS, with /bin/cat and /bin/sh available. These packages are unpublished. In an empty directory, install this exact source into the consumer's isolated Maven repository:

```console
$ git clone https://github.com/libtmux/libtmux-java libtmux-source && \
  git -C libtmux-source checkout --detach 5f88402151ff08fc0390dd438b90963692ec3fe4 && \
  (cd libtmux-source && ./gradlew \
    :libtmux:publishToMavenLocal \
    :libtmux-clojure:publishToMavenLocal \
    --console=plain \
    "-Dmaven.repo.local=$PWD/../m2")
```

Save this file as `deps.edn`. Dependencies resolve from the isolated m2 directory; the core.async dependency is only enabled by its alias.

[Source example](https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/examples/api/clojure/deps.edn).

```clojure
{:paths ["src/main/clojure"]
 :mvn/local-repo "m2"
 :deps {org.clojure/clojure {:mvn/version "1.12.6"}
        io.github.libtmux/libtmux-clojure {:mvn/version "0.1.2-SNAPSHOT"}}
 :aliases
 {:core-async
  {:extra-deps
   {io.github.libtmux/libtmux-clojure-core-async {:mvn/version "0.1.2-SNAPSHOT"}}}}}
```

Save this file as `run.sh`. The launcher creates and stops a private server, including after program failure, and reports leaked servers as errors.

[Source example](https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/examples/api/run.sh).

```sh
#!/bin/sh
set -eu

if [ "$#" -eq 0 ]; then
    printf 'Usage: sh run.sh program [arguments...]\n' >&2
    exit 2
fi
binary=$(command -v "${TMUX_BIN:-tmux}")
root=${API_RUN_ROOT:-/tmp/libtmux-java-dev}

# A client that names no socket follows TMUX or LIBTMUX_SOCKET*, and otherwise lands on the default
# socket under TMUX_TMPDIR. The program gets none of them, and a TMUX_TMPDIR of its own below.
unset TMUX TMUX_PANE
for name in $(env | sed -n 's/^\(LIBTMUX_SOCKET[A-Za-z0-9_]*\)=.*/\1/p'); do
    unset "$name"
done

mkdir -p "$root"
directory=$(mktemp -d "$root/api.XXXXXX")
tmpdir=$(mktemp -d "$root/tmpdir.XXXXXX")
socket="$directory/tmux.sock"
config="$directory/tmux.conf"

serves() {
    "$binary" -S "$1" display-message -p '#{pid}' >/dev/null 2>&1
}

# Stops the server on the socket, then waits for it to stop answering.
stop() {
    "$binary" -S "$1" kill-server || return 1
    attempts=0
    while serves "$1" && [ "$attempts" -lt 60 ]; do
        sleep 0.05
        attempts=$((attempts + 1))
    done
    ! serves "$1"
}

cleanup() {
    status=$?
    trap - 0 HUP INT TERM PIPE
    # A closed output must not end the cleanup, whose messages are the only thing left to write.
    trap '' PIPE
    set +e
    stuck=
    left=
    if [ -S "$socket" ] && serves "$socket" && ! stop "$socket"; then
        stuck="$stuck tmux.sock"
    fi
    # Every socket anywhere under either directory, without following links. Only one a server answers
    # on is a leak; the runner's own is expected to be there.
    old_ifs=$IFS
    IFS='
'
    set -f
    for candidate in $(find "$tmpdir" "$directory" -type s 2>/dev/null); do
        [ "$candidate" = "$socket" ] && continue
        serves "$candidate" || continue
        case "$candidate" in
            "$tmpdir"/*) name=${candidate#"$tmpdir"/} ;;
            *) name=${candidate#"$directory"/} ;;
        esac
        left="$left $name"
        stop "$candidate" || stuck="$stuck $name"
    done
    set +f
    IFS=$old_ifs
    if [ -n "$stuck" ]; then
        printf 'tmux still answers on%s after kill-server; kept %s and %s under the runner root\n' \
            "$stuck" "${directory##*/}" "${tmpdir##*/}" >&2
        exit 1
    fi
    rm -rf "$directory" "$tmpdir" || exit 1
    if [ -n "$left" ]; then
        printf 'The program left a tmux server running:%s\n' "$left" >&2
        exit 1
    fi
    exit "$status"
}
trap cleanup 0
trap 'exit 1' HUP INT TERM PIPE

# A default socket path longer than this does not fit in sun_path.
default_socket="$tmpdir/tmux-$(id -u)/default"
if [ "$(printf '%s' "$default_socket" | wc -c)" -gt 100 ]; then
    printf 'API_RUN_ROOT is too long for a tmux socket\n' >&2
    exit 1
fi
TMUX_TMPDIR=$tmpdir
export TMUX_TMPDIR

printf 'set-option -g default-shell /bin/sh\n' > "$config"
"$binary" -S "$socket" -f "$config" new-session -d -s work-one -n editor /bin/cat
"$binary" -S "$socket" split-window -h -t '=work-one:editor' /bin/cat
"$binary" -S "$socket" new-window -d -t '=work-one' -n logs /bin/cat
"$binary" -S "$socket" new-session -d -s work-two -n editor /bin/cat
"$@" "$binary" "$socket" "$config"
"$binary" -S "$socket" has-session -t '=work-one'
"$binary" -S "$socket" has-session -t '=work-two'
```

Save the complete program as `src/main/clojure/libtmux/examples/api/list_panes.clj`, creating its parent directories. Closing its client leaves the launcher's server running.

[Source example](https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/examples/src/main/clojure/libtmux/examples/api/list_panes.clj).

```clojure
(ns libtmux.examples.api.list-panes
  "Traverse session, window and pane observations without another acquisition."
  (:require [libtmux.core :as tm]
            [libtmux.data :as data]))

(defn -main [& args]
  (when-not (= 3 (count args))
    (throw (IllegalArgumentException. "expected: tmux-binary socket-path config-file")))
  (let [[binary socket config] args]
    (with-open [server (tm/open! {:binary binary :socket-path socket
                                 :config-file config})]
      (let [snapshot (tm/snapshot! server)
            session (data/exactly-one
                     (filter #(= "work-one" (:session/name %))
                             (:tmux/sessions snapshot)))
            window (data/exactly-one
                    (filter #(= "editor" (:window/name %)) (data/windows session)))]
        (println (str "panes=" (count (data/panes snapshot))))
        (println (str "window-panes=" (count (data/panes window))))))))
```

Run it with the private fixture. Set TMUX_BIN to select another tmux binary:

```console
$ sh run.sh clojure \
  -J-Dclojure.main.report=stderr \
  -M \
  -m libtmux.examples.api.list-panes
```

Expected output:

```text
panes=4
window-panes=2
```

Use a preserved Java Pane ref to read a command exit status and output. Use JDK 25 or newer, the Clojure CLI, Git and tmux on Linux or macOS, with /bin/cat and /bin/sh available. These packages are unpublished. In an empty directory, install this exact source into the consumer's isolated Maven repository:

```console
$ git clone https://github.com/libtmux/libtmux-java libtmux-source && \
  git -C libtmux-source checkout --detach 5f88402151ff08fc0390dd438b90963692ec3fe4 && \
  (cd libtmux-source && ./gradlew \
    :libtmux:publishToMavenLocal \
    :libtmux-clojure:publishToMavenLocal \
    --console=plain \
    "-Dmaven.repo.local=$PWD/../m2")
```

Save this file as `deps.edn`. Dependencies resolve from the isolated m2 directory; the core.async dependency is only enabled by its alias.

[Source example](https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/examples/api/clojure/deps.edn).

```clojure
{:paths ["src/main/clojure"]
 :mvn/local-repo "m2"
 :deps {org.clojure/clojure {:mvn/version "1.12.6"}
        io.github.libtmux/libtmux-clojure {:mvn/version "0.1.2-SNAPSHOT"}}
 :aliases
 {:core-async
  {:extra-deps
   {io.github.libtmux/libtmux-clojure-core-async {:mvn/version "0.1.2-SNAPSHOT"}}}}}
```

Save this file as `run.sh`. The launcher creates and stops a private server, including after program failure, and reports leaked servers as errors.

[Source example](https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/examples/api/run.sh).

```sh
#!/bin/sh
set -eu

if [ "$#" -eq 0 ]; then
    printf 'Usage: sh run.sh program [arguments...]\n' >&2
    exit 2
fi
binary=$(command -v "${TMUX_BIN:-tmux}")
root=${API_RUN_ROOT:-/tmp/libtmux-java-dev}

# A client that names no socket follows TMUX or LIBTMUX_SOCKET*, and otherwise lands on the default
# socket under TMUX_TMPDIR. The program gets none of them, and a TMUX_TMPDIR of its own below.
unset TMUX TMUX_PANE
for name in $(env | sed -n 's/^\(LIBTMUX_SOCKET[A-Za-z0-9_]*\)=.*/\1/p'); do
    unset "$name"
done

mkdir -p "$root"
directory=$(mktemp -d "$root/api.XXXXXX")
tmpdir=$(mktemp -d "$root/tmpdir.XXXXXX")
socket="$directory/tmux.sock"
config="$directory/tmux.conf"

serves() {
    "$binary" -S "$1" display-message -p '#{pid}' >/dev/null 2>&1
}

# Stops the server on the socket, then waits for it to stop answering.
stop() {
    "$binary" -S "$1" kill-server || return 1
    attempts=0
    while serves "$1" && [ "$attempts" -lt 60 ]; do
        sleep 0.05
        attempts=$((attempts + 1))
    done
    ! serves "$1"
}

cleanup() {
    status=$?
    trap - 0 HUP INT TERM PIPE
    # A closed output must not end the cleanup, whose messages are the only thing left to write.
    trap '' PIPE
    set +e
    stuck=
    left=
    if [ -S "$socket" ] && serves "$socket" && ! stop "$socket"; then
        stuck="$stuck tmux.sock"
    fi
    # Every socket anywhere under either directory, without following links. Only one a server answers
    # on is a leak; the runner's own is expected to be there.
    old_ifs=$IFS
    IFS='
'
    set -f
    for candidate in $(find "$tmpdir" "$directory" -type s 2>/dev/null); do
        [ "$candidate" = "$socket" ] && continue
        serves "$candidate" || continue
        case "$candidate" in
            "$tmpdir"/*) name=${candidate#"$tmpdir"/} ;;
            *) name=${candidate#"$directory"/} ;;
        esac
        left="$left $name"
        stop "$candidate" || stuck="$stuck $name"
    done
    set +f
    IFS=$old_ifs
    if [ -n "$stuck" ]; then
        printf 'tmux still answers on%s after kill-server; kept %s and %s under the runner root\n' \
            "$stuck" "${directory##*/}" "${tmpdir##*/}" >&2
        exit 1
    fi
    rm -rf "$directory" "$tmpdir" || exit 1
    if [ -n "$left" ]; then
        printf 'The program left a tmux server running:%s\n' "$left" >&2
        exit 1
    fi
    exit "$status"
}
trap cleanup 0
trap 'exit 1' HUP INT TERM PIPE

# A default socket path longer than this does not fit in sun_path.
default_socket="$tmpdir/tmux-$(id -u)/default"
if [ "$(printf '%s' "$default_socket" | wc -c)" -gt 100 ]; then
    printf 'API_RUN_ROOT is too long for a tmux socket\n' >&2
    exit 1
fi
TMUX_TMPDIR=$tmpdir
export TMUX_TMPDIR

printf 'set-option -g default-shell /bin/sh\n' > "$config"
"$binary" -S "$socket" -f "$config" new-session -d -s work-one -n editor /bin/cat
"$binary" -S "$socket" split-window -h -t '=work-one:editor' /bin/cat
"$binary" -S "$socket" new-window -d -t '=work-one' -n logs /bin/cat
"$binary" -S "$socket" new-session -d -s work-two -n editor /bin/cat
"$@" "$binary" "$socket" "$config"
"$binary" -S "$socket" has-session -t '=work-one'
"$binary" -S "$socket" has-session -t '=work-two'
```

Save the complete program as `src/main/clojure/libtmux/examples/api/run_a_command.clj`, creating its parent directories. Closing its client leaves the launcher's server running.

[Source example](https://github.com/libtmux/libtmux-java/blob/5f88402151ff08fc0390dd438b90963692ec3fe4/examples/src/main/clojure/libtmux/examples/api/run_a_command.clj).

```clojure
(ns libtmux.examples.api.run-a-command
  "Use the preserved Java Pane ref to observe a command's real exit status."
  (:require [clojure.string :as str]
            [libtmux.core :as tm]
            [libtmux.data :as data])
  (:import [io.github.libtmux Pane PaneRun PaneRun$Outcome]
           [java.time Duration]))

(defn -main [& args]
  (when-not (= 3 (count args))
    (throw (IllegalArgumentException. "expected: tmux-binary socket-path config-file")))
  (let [[binary socket config] args]
    (with-open [server (tm/open! {:binary binary :socket-path socket :config-file config})]
      (let [session (tm/new-session! server {:name "command-example" :command ["/bin/sh"]})
            ^Pane pane (:tmux/ref (data/exactly-one (data/panes session)))
            ^PaneRun result (.run pane "printf 'built\\n'; exit 3" (Duration/ofMillis 900))]
        (assert (= PaneRun$Outcome/FINISHED (.outcome result)))
        (assert (= 3 (.orElseThrow (.exitStatus result))))
        (assert (= ["built"] (vec (.output result))))
        (println (str "exit=" (.orElseThrow (.exitStatus result))
                      " output=" (str/join " / " (.output result))))))))
```

Run it with the private fixture. Set TMUX_BIN to select another tmux binary:

```console
$ sh run.sh clojure \
  -J-Dclojure.main.report=stderr \
  -M \
  -m libtmux.examples.api.run-a-command
```

Expected output:

```text
exit=3 output=built
```

## Parameters

- `value`

## Guides

Pages that discuss `panes`.

- [Server, session, window, pane](/en/clojure/latest/concepts/server-session-window-pane/)

## In other ports

A tmux pane

| Language | Equivalent |
| --- | --- |
| Python | [`libtmux.Pane`](/en/py/latest/reference/libtmux-pane/) (class) |
| Ruby | [`LibTmux::Pane`](/en/ruby/latest/reference/libtmux-pane-14z6/) (class) |
| Lua | [`libtmux.Pane`](/en/lua/latest/reference/libtmux-pane/) (class) |
| PowerShell | [`LibTmux\Get-TmuxPane`](/en/powershell/latest/reference/libtmux-get-tmuxpane/) (cmdlet). This cmdlet reads shared .NET `LibTmux.Pane` objects. Its [`-Server`](/en/powershell/latest/reference/libtmux-get-tmuxpane/#LibTmux%5CGet-TmuxPane.parameter.Server), [`-Session`](/en/powershell/latest/reference/libtmux-get-tmuxpane/#LibTmux%5CGet-TmuxPane.parameter.Session), and [`-Window`](/en/powershell/latest/reference/libtmux-get-tmuxpane/#LibTmux%5CGet-TmuxPane.parameter.Window) parameter sets select the scope. |
| Julia | [`LibTmux.PaneSnapshot`](/en/julia/latest/reference/libtmux-panesnapshot/) (struct). `PaneSnapshot` holds captured pane data. Actions use its `PaneRef`; `PaneOccurrence` adds a window placement in a session. |
| Erlang | [`#tmux_model:pane{}`](/en/erlang/latest/reference/tmux_model-pane/) (struct) |
| Elixir | [`LibTmux.Pane`](/en/elixir/latest/reference/libtmux-pane/) (struct). `Pane` is an immutable physical pane observation. It does not send keys or capture text. |
| Haskell | No public Haskell equivalent is implemented; the current modules expose scalar values and version parsing. |
| Common Lisp | [`libtmux:pane`](/en/lisp/latest/reference/libtmux-pane/) (class). `pane` is an immutable captured physical pane. |
| TypeScript | [`pane.Pane`](/en/ts/latest/reference/pane-pane/) (class) |
| Rust | [`pane.Pane`](/en/rs/latest/reference/pane-pane/) (struct) |
| Go | [`tmux.Pane`](/en/go/latest/reference/tmux-pane/) (struct) |
| Java | [`io.github.libtmux.Pane`](/en/java/latest/reference/io-github-libtmux-pane-pane/) (class) |
| Kotlin | [`io.github.libtmux.kotlin.Pane`](/en/kotlin/latest/reference/io-github-libtmux-kotlin-pane/) (class) |
| Scala | [`io.github.libtmux.scaladsl.Pane`](/en/scala/latest/reference/io-github-libtmux-scaladsl-pane/) (typealias) |
| C# | [`LibTmux.Pane`](/en/csharp/latest/reference/libtmux-pane/) (class) |
| F# | [`LibTmux.FSharp.Pane`](/en/fsharp/latest/reference/libtmux-fsharp-pane/) (module). This F# module reads captured fields and starts explicit operations on the shared .NET `LibTmux.Pane` type. |
| C++ | [`libtmux::Pane`](/en/cxx/latest/reference/libtmux-pane/) (class) |
| Swift | [`Pane`](/en/swift/latest/reference/pane/) (struct) |
| OCaml | [`Libtmux.Pane.t`](/en/ocaml/latest/reference/libtmux-pane-t/) (typealias) |
| Perl | [`LibTmux::Pane`](/en/perl/latest/reference/libtmux-pane/) (class). A physical pane retains its captured graph, without retaining transport. |

List a window's panes

| Language | Equivalent |
| --- | --- |
| Python | [`libtmux.Window.panes`](/en/py/latest/reference/libtmux-window-panes/) (property) |
| Ruby | [`LibTmux::Window#list_panes`](/en/ruby/latest/reference/libtmux-window-list_panes/) (method) |
| PowerShell | [`LibTmux\Get-TmuxPane`](/en/powershell/latest/reference/libtmux-get-tmuxpane/) (cmdlet). Use the [`-Window`](/en/powershell/latest/reference/libtmux-get-tmuxpane/#LibTmux%5CGet-TmuxPane.parameter.Window) parameter set to acquire panes in one window. |
| Julia | [`LibTmux.panes`](/en/julia/latest/reference/libtmux-panes/) (function). `panes` with a captured `WindowSnapshot` reads panes in that window; missing coverage is an error. |
| Erlang | [`tmux_snapshot:related/3`](/en/erlang/latest/reference/tmux_snapshot-related-3/) (function). Pass `panes`, a captured physical window and its snapshot for a local relationship read. |
| Haskell | No public Haskell equivalent is implemented; the current modules expose scalar values and version parsing. |
| Common Lisp | [`libtmux:panes`](/en/lisp/latest/reference/libtmux-panes/) (function). `panes` traverses a captured window without contacting tmux. |
| TypeScript | [`window.Window.panes`](/en/ts/latest/reference/window-window-panes/) (method) |
| Rust | [`window.Window.panes`](/en/rs/latest/reference/window-window-panes/) (method) |
| Go | [`tmux.Window.Panes`](/en/go/latest/reference/tmux-window-panes/) (method) |
| Java | [`io.github.libtmux.Window.panes`](/en/java/latest/reference/io-github-libtmux-window-window-panes/) (method) |
| Kotlin | [`io.github.libtmux.kotlin.Window.panes`](/en/kotlin/latest/reference/io-github-libtmux-kotlin-window-panes/) (property) |
| Scala | [`io.github.libtmux.scaladsl.Window.panes`](/en/scala/latest/reference/io-github-libtmux-scaladsl-window-panes/) (method) |
| C# | [`LibTmux.Window.Panes`](/en/csharp/latest/reference/libtmux-window-panes/) (property) |
| F# | [`LibTmux.FSharp.Window.panes`](/en/fsharp/latest/reference/libtmux-fsharp-window-panes/) (function). Builds a deferred pane query from one `LibTmux.Window` and its server. `Query.list` acquires panes scoped to that window ID. |
| C++ | [`libtmux::Window::panes`](/en/cxx/latest/reference/libtmux-window-panes/) (method) |
| Swift | [`Snapshot.panes(of:)`](/en/swift/latest/reference/snapshot-panes(of-)/) (method) |
| OCaml | [`Libtmux.Window.panes`](/en/ocaml/latest/reference/libtmux-window-panes/) (function). Reads captured panes in one global window without I/O. |
| Perl | [`LibTmux::Window::panes`](/en/perl/latest/reference/libtmux-window-panes/) (method). Reads this physical window’s captured panes without I/O. |

No equivalent is recorded in Lua or Elixir.