Function svn_relpath_get_longest_ancestor 

pub unsafe extern "C" fn svn_relpath_get_longest_ancestor(
    relpath1: *const c_char,
    relpath2: *const c_char,
    result_pool: *mut apr_pool_t,
) -> *mut c_char

Return the longest common path shared by two relative paths, @a relpath1 and @a relpath2. If there’s no common ancestor, return the empty path.

Allocate the result in @a result_pool.

@since New in 1.7.