# Pane configuration

Source: https://libtmux.org/en/dotnet/latest/workspace/configuration/panes/

> Tmuxp pane configuration and current .NET builder compatibility.

**tmuxp compatibility reference.** Examples using `tmuxp` run the Python reference. [Local CLI status](../../reference/compatibility/) describes this port's implemented coverage.

A pane can be a command string, a list of commands, or a mapping of settings.
Each item in the window's `"panes"` list creates one pane; a command list inside
that item describes several commands in that same pane.

The native .NET CLI creates panes in configuration order. This also holds for
windows with three or more panes: each new split follows the preceding pane.
`pane-base-index` changes their starting index; `focus: true` selects a
configured pane without changing creation order. Layouts determine the final
geometry. See the [native load source](https://github.com/libtmux/libtmux-dotnet/blob/4ac82a5b82fd8cf68d31c70a2a3eb43c587cd7c0/src/LibTmux.Workspace.Cli/ExecutionCommands.cs).

```yaml
session_name: pane-example
start_directory: ./
windows:
  - window_name: main
    start_directory: ./
    panes:
      - echo one command
      - [echo first command, echo second command]
      - shell_command:
          - echo configured pane
        start_directory: ./
        focus: true
      - blank
```

## Blank forms

| Form inside `"panes"` | Reference interpretation |
| --- | --- |
| null, omitted YAML value, `blank`, or `"pane"` | Pane without its own commands |
| Empty mapping or empty list | Expands to a pane without its own commands |
| Mapping with no shell_command | Keeps the pane's other settings and uses no own commands |
| `shell_command: null` or a single null command | No own commands |
| Empty string `""` | Sends an empty command, normally pressing Enter |

A blank pane can still receive inherited [before commands](../commands/). Blank
forms do not disable session/window/pane setup. An omitted window panes key is
defaulted to one blank pane; an explicitly empty panes list is a different shape
and should not be used as a portable way to request that default.

## Pane keys

| Key | Meaning |
| --- | --- |
| `shell_command` | String, ordered command list, or supported command dictionaries |
| `shell_command_before` | Setup prepended after session/window before commands |
| `start_directory` | Pane directory override |
| `"shell"` | Shell/application launched for this pane |
| `focus` | Select this pane in its window |
| `"environment"` | Environment map selected for this pane's launch |
| `"suppress_history"` | Pane history policy override |
| `"enter"` | Default for whether to submit each command |
| `sleep_before`, `sleep_after` | Default delays in seconds around each command |

## Launch a shell or type commands

`"shell"` chooses the process tmux starts in the pane. `shell_command` sends text
into the process already running there. Launching an application through shell
can work with tmux's remain-on-exit behavior, while typing that application's
name into a shell has different process semantics.

A pane shell overrides window_shell, including on the first pane. The first pane
also supplies its directory and environment during window creation. Use an
installed shell/application path rather than assuming the same executable exists
on every host.

A successful build confirms command delivery, not application readiness or
command exit status. See [commands](../commands/) for Enter, timing, and
history, and [environment](../environment/) for launch-map selection.

## Current .NET builder

Pane values support the package's command and directory shapes. The full set of
tmuxp shorthand, shell, environment, and command-mapping forms is not accepted.

See the [native builder behavior](../../internals/topics/) and [configuration
source](https://github.com/libtmux/libtmux-dotnet/blob/b71b9654f41785c93717e454cbf176672b3d634a/src/LibTmux.Workspace/WorkspaceYamlParser.cs)
before using these fields through application code.

## Reference source

[loader.py](https://github.com/tmux-python/tmuxp/blob/618b398acc05506d3c682906c36cdeb29dcfa1ff/src/tmuxp/workspace/loader.py); [classic.py](https://github.com/tmux-python/tmuxp/blob/618b398acc05506d3c682906c36cdeb29dcfa1ff/src/tmuxp/workspace/builder/classic.py); [blank-panes.yaml](https://github.com/tmux-python/tmuxp/blob/618b398acc05506d3c682906c36cdeb29dcfa1ff/examples/blank-panes.yaml); [pane-shell.yaml](https://github.com/tmux-python/tmuxp/blob/618b398acc05506d3c682906c36cdeb29dcfa1ff/examples/pane-shell.yaml).