# LibTmux::Server#new_session

- **Module:** LibTmux
- **Package:** libtmux
- **Language:** Ruby
- **Kind:** method
- **Source:** https://github.com/libtmux/libtmux-ruby/blob/da7b6191b9439e3c84fa1c9eeaa9168263ee7af4/gems/libtmux/lib/libtmux/server.rb#L252
- **Page:** https://libtmux.org/en/ruby/v0.1.1/reference/libtmux-server-new_session/

```
def new_session: (
  name: ::String,
  command: ::Array[::String],
  receipt: true,
  ?width: ::Integer?,
  ?height: ::Integer?,
  ?window_name: ::String?,
  ?cwd: ::String?,
  ?environment: ::Hash[::String, ::String],
  ?timeout: ::Numeric,
  ?cancel: untyped
) -> ::LibTmux::CreationReceipt

def new_session: (
  name: ::String,
  command: ::Array[::String],
  ?receipt: false,
  ?width: ::Integer?,
  ?height: ::Integer?,
  ?window_name: ::String?,
  ?cwd: ::String?,
  ?environment: ::Hash[::String, ::String],
  ?timeout: ::Numeric,
  ?cancel: untyped
) -> ::LibTmux::Session
```

Behavior: Creation.

Behavior contract: Creation.

## Examples

Start a private server and create a session. Request a creation receipt to read the session, window, and pane IDs returned by that creation command. Use Ruby 3.3 or newer with Bundler, and tmux 3.3a or newer, on Unix with `/bin/cat` and `/bin/sh` available. In an empty directory, save this `Gemfile`:

```ruby
source "https://rubygems.org"

gem "libtmux", "0.1.1"
```

Save this complete program as `new_session.rb`. Its `Server.start` block owns a private tmux server and stops it on exit, including after an error.

[Source example](https://github.com/libtmux/libtmux-ruby/blob/da7b6191b9439e3c84fa1c9eeaa9168263ee7af4/examples/api/new_session.rb).

```ruby
# frozen_string_literal: true

begin
  # docs:begin main
  require "libtmux"

  LibTmux::Server.start do |server|
    created = server.new_session(
      name: "work", window_name: "main", command: ["/bin/cat"], receipt: true
    )
    puts "session: #{created.entity.id}"
    puts "window: #{created.window.id}"
    puts "pane: #{created.pane.id}"
  end
  # docs:end main
rescue StandardError => error
  warn "#{error.class}: #{error.message}"
  exit 1
end
```

Install the gem and run the program. An operation or cleanup error makes it exit unsuccessfully:

```console
$ bundle install && \
  bundle exec ruby new_session.rb
```

Expected output:

```text
session: $0
window: @0
pane: %0
```

## Parameters

- `name` (`::String`)
- `command` (`::Array[::String]`)
- `receipt` (`true`) (for `new_session(name, command, receipt, width, height, window_name, cwd, environment, timeout, cancel) [overload 1]`)
- `width` (`::Integer?`)
- `height` (`::Integer?`)
- `window_name` (`::String?`)
- `cwd` (`::String?`)
- `environment` (`::Hash[::String, ::String]`)
- `timeout` (`::Numeric`)
- `cancel` (`untyped`)
- `receipt` (`false`) (for `new_session(name, command, receipt, width, height, window_name, cwd, environment, timeout, cancel) [overload 2]`)

## tmux command

The tmux commands behind `new_session`.

- [`new-session`](/en/tmux/latest/manual/new-session/)

## tmux C API

The C declarations in tmux that implement these commands.

- [`cmd_new_session_entry`](/en/tmux/latest/reference/c-variable-cmd_new_session_entry/) (attribute)
- [`cmd_new_session_exec`](/en/tmux/latest/reference/c-function-cmd-new-session-c-cmd_new_session_exec/) (function)

Each path starts at a function a command runs, which is degree 1. The degree counts steps from there along the path, and each step is a call or a reference: degree 2 is reached from that function, degree 3 from the next, and so on.

### Create a session and its first pane

1. [`cmd_new_session_exec`](/en/tmux/latest/reference/c-function-cmd-new-session-c-cmd_new_session_exec/) (function)
2. calls → [`spawn_window`](/en/tmux/latest/reference/c-function-spawn_window/) (function)
3. calls → [`spawn_pane`](/en/tmux/latest/reference/c-function-spawn_pane/) (function)
4. calls → [`window_add_pane`](/en/tmux/latest/reference/c-function-window_add_pane/) (function)
5. calls → [`window_pane_create`](/en/tmux/latest/reference/c-function-window-c-window_pane_create/) (function)

## In other ports

Create a session

| Language | Equivalent |
| --- | --- |
| Python | [`libtmux.Server.new_session`](/en/py/latest/reference/libtmux-server-new_session/) (method) |
| Lua | [`libtmux.Server:new_session`](/en/lua/latest/reference/libtmux-server-new_session/) (method) |
| TypeScript | [`server.Server.newSession`](/en/ts/latest/reference/server-server-newsession/) (method) |
| Rust | [`server.Server.new_session`](/en/rs/latest/reference/server-server-new_session/) (method) |
| Go | [`tmux.Server.NewSession`](/en/go/latest/reference/tmux-server-newsession/) (method) |
| Java | [`io.github.libtmux.Server.newSession`](/en/java/latest/reference/io-github-libtmux-server-server-newsession/) (method) |
| Kotlin | [`io.github.libtmux.kotlin.Server.newSession`](/en/kotlin/latest/reference/io-github-libtmux-kotlin-server-newsession/) (method) |
| Scala | [`io.github.libtmux.scaladsl.Server.newSession`](/en/scala/latest/reference/io-github-libtmux-scaladsl-server-newsession/) (method) |
| C# | [`LibTmux.Server.CreateSessionAsync`](/en/csharp/latest/reference/libtmux-server-createsessionasync/) (method) |
| C++ | [`libtmux::Server::new_session`](/en/cxx/latest/reference/libtmux-server-new_session/) (method) |
| Swift | [`Server.newSession(named:startDirectory:windowName:width:height:environment:shell:)`](/en/swift/latest/reference/server-newsession(named-startdirectory-windowname-width-height-)/) (method) |

No equivalent is recorded in PowerShell, Julia, Elixir or F#.