lib/ecdsa.c
// return 1 if P is on curve E
return 1 if P is on curve E
return 1 if P is on curve E
int ison(epnt p) {
  long r;
  long s;
  if (!isO(p)) {
    r = modn(e.b + p.x * modn(e.a + p.x * p.x));
    s = modn(p.y * p.y);
  }
  return (r == s);
}
int ison ( epnt p ) { long r ; long s ; if ( ! isO ( p ) ) { r = modn ( e . b + p . x * modn ( e . a + p . x * p . x ) ) ; s = modn ( p . y * p . y ) ; } return ( r == s ) ; }
return 1 if P is on curve E
return 1 if P is on curve E