# session.Session.append_option

- **Module:** session.Session
- **Package:** libtmux
- **Language:** Rust
- **Kind:** method
- **Source:** https://github.com/libtmux/libtmux-rs/blob/f0e37052c232636b61d095817046e6bfc8f2ca40/crates/libtmux/src/session/settings.rs#L168
- **Page:** https://libtmux.org/en/rs/latest/reference/session-session-append_option/

```
session.Session.append_option(self, name: &str, value: impl Into<OsString>) -> Result<(), Error>
```

Append to one option rather than replacing it.

# Errors

Returns an error when tmux rejects the name or value.

Returns [`crate::Error::OptionScopeMismatch`] when tmux keeps the
option in another of its tables.