Function ncplane_contents 

pub unsafe extern "C" fn ncplane_contents(
    n: *mut ncplane,
    begy: c_int,
    begx: c_int,
    leny: c_uint,
    lenx: c_uint,
) -> *mut c_char

Create a flat string from the EGCs of the selected region of the ncplane ‘n’. Start at the plane’s ‘begy’x’begx’ coordinate (which must lie on the plane), continuing for ‘leny’x’lenx’ cells. Either or both of ‘leny’ and ‘lenx’ can be specified as 0 to go through the boundary of the plane. -1 can be specified for ‘begx’/‘begy’ to use the current cursor location.