# types.CaptureOptions.alternateScreen

- **Module:** types.CaptureOptions
- **Package:** @libtmux/libtmux
- **Language:** TypeScript
- **Kind:** property
- **Source:** https://github.com/libtmux/libtmux-ts/blob/2cb93308200da38a26b59876618116850f110607/packages/libtmux/src/types.ts#L328
- **Page:** https://libtmux.org/reference/ts/types-captureoptions-alternatescreen/

Capture the screen saved underneath a full-screen program, tmux's `-a`.

Not what that program is displaying — an ordinary capture already reads
that, because the program's display is the pane's visible grid. tmux saves
the *normal* screen when a program switches to the alternate one
(`screen_alternate_on` copies the grid into `saved_grid`, which is what
`-a` reads), so this answers with what an editor or a pager is covering
up, not with the editor or the pager.

It exists only while such a program is running: tmux frees the saved grid
when the program leaves the alternate screen, and fails with "no alternate
screen" whenever there is nothing on it.