Function secp256k1_zkp_sys::secp256k1_ecdh

pub unsafe extern "C" fn secp256k1_ecdh(
    cx: *const Context, 
    output: *mut u8, 
    pubkey: *const PublicKey, 
    seckey: *const u8, 
    hashfp: Option<unsafe extern "C" fn(*mut u8, *const u8, *const u8, *mut c_void) -> i32>, 
    data: *mut c_void
) -> i32