Function ghostty_focus_encode 

pub unsafe extern "C" fn ghostty_focus_encode(
    event: Type,
    buf: *mut c_char,
    buf_len: usize,
    out_written: *mut usize,
) -> Type

Encode a focus event into a terminal escape sequence.

Encodes a focus gained (CSI I) or focus lost (CSI O) report into the provided buffer.

If the buffer is too small, the function returns GHOSTTY_OUT_OF_SPACE and writes the required buffer size to @p out_written. The caller can then retry with a sufficiently sized buffer.

        GHOSTTY_OUT_OF_SPACE, the required buffer size.
    is too small