Link message

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Description

Event: link_message( integer sender_num, integer num, string str, key id ){ ; }

Triggered when the script receives a link message that was sent by a call to llMessageLinked. llMessageLinked is used to send messages from one script to another.

• integer sender_num The link number of the prim that contained the script that called llMessageLinked.
• integer num Second parameter of the llMessageLinked call.
• string str The message that was sent from the script that called llMessageLinked.
• key id Fourth parameter of the llMessageLinked call.

id is often used as a second string field (in LSL the key type is implemented as a string with just custom operators). Typecasting between string and key types has no effect on the data contained. The sizes of str and id are only limited by available script memory.

Caveats

  • 64 link_message events can queue, past that, they are silently dropped! Don't do too much in the event if they might be coming in fast.
  • sender_num does not reflect how a message was sent, there is no way to know if it was sent with a LINK_* flag or the specific link number.
  • If str and id are bigger than available memory the script will crash with a Stack-Heap Collision.
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Examples

//This is just an example script, you shouldn't handle touches within single script this way.
 
default
{
    touch_start(integer num_detected)
    {
        llMessageLinked(LINK_THIS, 0, llDetectedName(0), llDetectedKey(0));
    }
 
    link_message(integer source, integer num, string str, key id)
    {
        llWhisper(0, str + " (" + (string)id + ") touched me!");
    }
}

Useful Snippets

// This is just an example script, you shouldn't handle link message within single script this way.
 
default
{
     // To propagate an unlimited number of arguments of any type.
     // Presumed, the separator string isn't used in any source string!
 
    state_entry() 
    {    
        list my_list = [1, 2.0, "a string", <1, 2, 3>, <1, 2, 3, 4>, llGetOwner()];  
        string list_parameter = llDumpList2String(my_list, "|");	// Produce a | delimited string from the list
        llMessageLinked(LINK_THIS, 0, list_parameter, NULL_KEY);
    }
 
    link_message(integer sender_num, integer num, string list_argument, key id) 
    {
        list re_list = llParseString2List(list_argument, ["|"], [""]);	// Convert the string back to a list
    }    
}

Notes

KBcaution.png Important: A script can hear its own link messages.

See Also

Functions

•  llMessageLinked

Deep Notes

Signature

event void link_message( integer sender_num, integer num, string str, key id );
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