Function svn_checksum_update 

pub unsafe extern "C" fn svn_checksum_update(
    ctx: *mut svn_checksum_ctx_t,
    data: *const c_void,
    len: apr_size_t,
) -> *mut svn_error_t

Update the checksum represented by @a ctx, with @a len bytes starting at @a data.

@since New in 1.6.