public static byte[] string_append_3( byte[] o1, byte[] o2, byte[] o3 )
{
int n1= o1.Length;
int n2= o2.Length;
int n3= o3.Length;
byte[] r= new byte[n1 + n2 + n3];
bcopy( o1, 0, r, 0, n1 );
bcopy( o2, 0, r, n1, n2 );
bcopy( o3, 0, r, n1+n2, n3 );
return r;
}