libtmux.Window.split

start_directory ( StrPath | None ) – Specifies the working directory in which the new window is created.

attach ( bool ) – Make new window the current window after creating it, default True.

direction ( PaneDirection | None ) – Split in direction. If none is specified, assume down.

full_window_split ( bool | None ) – Split across full window width or height, rather than active pane.

zoom ( bool | None ) – Expand pane.

shell ( str | None ) – Execute a command on splitting the window. The pane will close when the command exits. NOTE: When this command exits the pane will close. This feature is useful for long-running processes where the closing of the window upon completion is desired.

size ( str | int | None ) – Cell/row count to occupy with respect to current window.

percentage ( int | None ) – Percentage (0-100) of the window to occupy (-p flag). Mutually exclusive with *size*. added 0.56

environment ( dict[str, str] | None ) – Environmental variables for new pane. Passthrough to -e.

empty ( bool | None ) – Create an empty pane with no command (-E flag) instead of spawning the default shell. Requires tmux 3.7+. If used with tmux < 3.7, a warning is issued and the flag is ignored.

style ( str | None ) – Style for the new pane (-s). Requires tmux 3.7+.

active_border_style ( str | None ) – Active-pane border style (-S). Requires tmux 3.7+.

inactive_border_style ( str | None ) – Inactive-pane border style (-R). Requires tmux 3.7+.

message ( str | None ) – Keep the pane open (until a key is pressed) after exit, showing this remain-on-exit-format message (-m). Requires tmux 3.7+.

keep ( bool | None ) – Keep the pane open until a key is pressed after exit (-k). Requires tmux 3.7+. These 3.7 flags warn and are ignored below 3.7.