Changed

Various changes to the object/prim trigger this event.

Multiple changes can be represented in a single event, so use bitwise arithmetic.

default
{
    changed(integer change)
    {
        //note that it's & and not &&... it's bitwise!
        if (change & CHANGED_INVENTORY)         
        {
            llOwnerSay("The inventory has changed.");
        }
        if (change & CHANGED_COLOR) 
        {
            llOwnerSay("The color or alpha changed.");
        }
        if (change & CHANGED_SHAPE) 
        {
            llOwnerSay("The prims shape has changed.");
        }
        if (change & CHANGED_SCALE) 
        {
            llOwnerSay("The prims size has changed.");
        }
        if (change & CHANGED_TEXTURE) 
        {
            llOwnerSay("The prims texture or texture attributes have changed.");
        }
        if (change & CHANGED_LINK) 
        {
            llOwnerSay("The number of links have changed.");
        }
        if (change & CHANGED_ALLOWED_DROP) 
        {
            llOwnerSay("The inventory has changed as a result of a user without mod permissions "+
                       "dropping an item on the prim and it being allowed by the script.");
        }
        if (change & CHANGED_OWNER) 
        {
            llOwnerSay("The owner of the object has changed.");
        }
        if (change & CHANGED_REGION) 
        {
            llOwnerSay("The region the object is in has changed.");
        }
        if (change & CHANGED_TELEPORT) 
        {
            llOwnerSay("The object has been teleported while attached.");
        }
        if (change & CHANGED_REGION_START) 
        {
            llOwnerSay("The regions has just restarted.");
        }
    }
}

For the same action to be called for multiple changes we can use the following syntax.

default
{
    changed(integer change)
    {
        if(change & (CHANGED_OWNER | CHANGED_INVENTORY)) // Either of the changes will return true.
            llResetScript();
    }
}

• Always test the value of change unless you want your script to act upon any change that triggers it.
  • New CHANGED_* flags, bugs and bug fixes could conceivably be added by LL at any time. Scripts should be written under the assumption that they will receive changed events not expected at the time or place of writing. For future proof scripts, use bitwise conditions as in the examples.
• See llGetOwner for a full discussion on " (change & CHANGED_OWNER) "
• If leaving a state from within a changed event that registers a change just before the state change, on return to that state the changed event will trigger. For example -

default
{
    changed(integer change)
    {
        if(change & CHANGED_LINK)
        {
            integer links = 0;
            if(llGetObjectPrimCount(llGetKey()) < (links = llGetNumberOfPrims()))
            {
                llUnSit(llGetLinkKey(links));
                state whatever;
            }
            else
            llOwnerSay("Some kind of linking or unlinking has changed me but, I am not being sat on.");
            // This will be chatted after returning to the default state.
        }
    }
}
state whatever
{
    state_entry()
    {
        llSetTimerEvent(10.0);
    }
    timer()
    {
        state default;
    }
}