I got the old pathfinding script from http://www.arongranberg.com/unity/pathfinding/ but it uses a clicked point where to move to, but i don't know what is to be changed, so that i don't have to click the enemy first and a end point, i want an enemy to follow the player at all time.. anyone can help?

Here's the script:

// Copyright 2009 - Aron Granberg - aron.g@me.com

//This is version 0.5 of the script

var points : Array;//The nods
var pathlength : float = 0;
var giz = false;
var mask : LayerMask;//Use this to avoid raycasting units or terrain
var minimumdistance : float = 3;//The minimum distance from the target it must be to get finished.
private var level = 0;
private var maxloops = 40;//The max number of times the findpath function can be called (to prevend hanging)
var debugg = true;
function startFind (fpos : Vector3, pos : Vector3, margin : float) {//This is the function you shall call, don't call fundPath function
    giz = false;
    points = new Array();
    points.Add (fpos);
    level = 0;
    findPath (fpos,pos, margin,Vector3.zero);//Calculate the path
    yield WaitForEndOfFrame ();
    giz =true;
    var r = points.ToBuiltin(Vector3);
    var re = GetComponent (AI);//This is the script for the units
    if (re) {//Does it have the AI script attahed
        re.points = r;
        re.FindPoint (0);
    }
}
function findPath (fpos : Vector3 , pos : Vector3, margin : float,contwith : Vector3) {
    level += 1;
    if (level > maxloops) {//Just so it does not hang if the point is in a ungetable place (like inside a box)
        //print ("Chrash Protection, to many loops");
        return;
    }
    if (Vector3.Distance (fpos, pos) < minimumdistance) {//Is it there yet
        if (contwith != Vector3.zero) {
            findPath (fpos,contwith,margin,Vector3.zero);
        } else {
            return;
        }
    }
    var hits : RaycastHit[]; 
    var hit : RaycastHit;
    var p : Vector3 = pos - fpos;
    hits = Physics.RaycastAll (fpos, p, p.magnitude, mask);//Objects between start and target
    if (hits.length == 0) {//If we can see the target it is just to go straight to it
        Debug.DrawLine (fpos, pos, Color.green);
        points.Add (pos);
        if (debugg)
            //print ("Free Way");

        pathlength = 0;
        for (i = 0;i<points.length-1;i++) {
            pathlength += Vector3.Distance (points[i],points[i+1]);
        }
        return;
    }
    Debug.DrawLine (fpos, pos, Color.red);
    var gos = new Array ();
    for (i=0;i<hits.length;i++) {
        //print (hits[i].transform.gameObject.name);
        gos.Add (hits[i].transform.gameObject);//Put them in a array
    }
    var mindist = Mathf.Infinity;
    for (i=0;i<gos.length;i++) {
        dist = Vector3.Distance (fpos, gos[i].transform.position);
        if (dist < mindist) {
            tg = gos[i];// The nearest gameObject
        }
    }
    point =  findpoint (tg,fpos, pos, margin);
    if (point == Vector3.zero) {//If findpoint function returned zero it failed
        if (debugg)
            print ("Failed");

        return;
    }
    if (point == Vector3.one) {//If findpoint function returned zero it failed
        return;
    }
    points.Add (point);//Add the calculated point and run the function again
    findPath (points[points.length-1], pos ,margin,contwith);

}
var cubep : Array;//Just an array
function findpoint (tg : GameObject, fpos : Vector3, pos : Vector3, margin : float) : Vector3 {
    cubep.Clear ();
    bo = tg.collider.bounds;
    ext = bo.extents;
    ext.y = 0;
    cubep.Add ( bo.center + ext + (ext.normalized * margin));
    ext = bo.extents;
    ext.y = 0;
    ext.x = -ext.x;
    cubep.Add ( bo.center + ext + (ext.normalized * margin));
    ext = bo.extents;
    ext.y = 0;
    ext.z = -ext.z;
    cubep.Add ( bo.center + ext + (ext.normalized * margin));
    ext = bo.extents;
    ext.y = 0;
    ext.x = -ext.x;
    ext.z = -ext.z;
    cubep.Add ( bo.center + ext + (ext.normalized * margin));//Calculate 4 points around the object and add a margin

    v = new Array ();
    for (i=0;i<cubep.length;i++) {
        if (cubep[i] != points[points.length-1]) {
            if (!Physics.Linecast (fpos,cubep[i], mask)) {///Is the point visible from here?
                Debug.DrawLine (fpos,cubep[i], Color.green);
                Debug.DrawRay (fpos,cubep[i].normalized * 40,Color.red);
                v.Add (cubep[i]);
            } else {
                Debug.DrawLine (fpos,cubep[i], Color.red);
            }
        }
    }
    if (v.length == 0) {//We can't see any points, then calculate the path to the best point
        var px : Vector3 = findpossiblepoints (pos,fpos,tg,cubep);
        findPath (fpos,px,margin,pos);
        return Vector3.one;
    }
    var mindist : float = Mathf.Infinity;
    var point = Vector3.zero;
    for (i=0;i<v.length;i++) {
        var d : float = Vector3.Distance (pos,v[i]);//Which one is closest?
        if (d < mindist) {
            mindist = d;
            point = v[i];
        }
    }
    return point;
}
function findpossiblepoints (pos : Vector3,fpos : Vector3, tg : GameObject, cubep : Array) : Vector3 {
    //print ("Help called");
    var v = new Array();
    for (i=0;i<cubep.length;i++) {
        var dir : Vector3 = cubep[i] - fpos;
        var ra : Ray = Ray (fpos,dir);
        if (!tg.collider.bounds.IntersectRay(ra)) {//Is it intersecting the tg/Should it be visible (if it wasent some things in the way)
            v.Add (cubep[i]);
            Debug.DrawRay(fpos,dir,Color.yellow);
        }
    }
    var mindist : float = Mathf.Infinity;
    var point = Vector3.zero;
    for (i=0;i<v.length;i++) {
        var d : float = Vector3.Distance (pos,v[i]);//Which one is closest?
        if (d < mindist) {
            mindist = d;
            point = v[i];
        }
    }
    return point;
}
function Awake () {
    giz = true;
    points = new Array();
    cubep = new Array();
}
function Update () {
    for (i = 0;i<points.length-1;i++) {
        Debug.DrawLine (points[i],points[i+1],Color.red);
    }
}
function OnDrawGizmos () {//Just some debug info
    if (giz && debugg) {
    for (i = 0;i<points.length-1;i++) {
        Gizmos.color = Color.green;
        Gizmos.DrawLine (points[i], points[i+1]);
        Gizmos.color = Color.yellow;
        Gizmos.DrawSphere (points[i], 0.5);
    }
    for (i = 0;i<cubep.length;i++) {
        if (i==0) {
            Gizmos.color = Color.red;
        } else {
            Gizmos.color = Color.green;
        }
        Gizmos.DrawSphere (cubep[i], 0.5);
    }
    }
}