sensor

Hacked two scripts together thinking it would work but...well it doesn't work. I get an error at sensor(integer det)
Any help?
Oh, and how can I get it to follow who I choose and not just is the close one. This is controled on and off from a seperate prim.

integer chan = -27296; 


default
{
        state_entry()
        {
                llListen(chan, "", NULL_KEY, "");
        }

        listen( integer channel, string name, key id, string message )
        {
                if ( message == "On" )
                
                
                {
                        llSensorRepeat("","",AGENT,10,PI,.1);
                }
                
                       sensor(integer det)

                {

                      vector pos = llDetectedPos(0);
 
                      llLookAt(pos,1,1); 

                }
            
            
                else  if ( message == "Off" )
                {
                        llSensorRemove();
                }
                
                
        }
} 

You have your code all mixed up, the sensor should be in the default state, but not in the listener event:

integer chan = -27296; 

default{
    state_entry(){
        llListen(chan, "", NULL_KEY, "");
    }

    listen( integer channel, string name, key id, string message ){
        if ( message == "On" ){
            llSensorRepeat("",NULL_KEY,AGENT,10,PI,.1);
        }
        else  if ( message == "Off" ){
            llSensorRemove();
        }
    }
                
    sensor(integer det){
        vector pos = llDetectedPos(0);
        llLookAt(pos,1,1); 
    }
}

To have it follow the person you choose, you need to add their key or name in the sensor call. As you have it, it's scanning for all agents.