查看“虚拟世界/脚本间通信”的源代码

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===llMessageLinked( integer link, integer num, string str, key id )===
该脚本目的是允许一个物体中脚本之间进行通信。它将触发link_message事件，事件相关参数num、str、id相同，捕获到的元件由link参数决定。
#integer link: Link number (0: unlinked, 1: root prim, >1: child prims and seated avatars) or a LINK_* flag, controls which prim(s) receive the link_message.	
#integer num: Value of the second parameter of the resulting link_message event.	
#string	str: Value of the third parameter of the resulting link_message event.	
#key id: Value of the fourth parameter of the resulting link_message event.	
<pre>
LINK_ROOT	1	sends to the root prim in a multi-prim linked set[1]
LINK_SET	-1	sends to all prims
LINK_ALL_OTHERS	-2	sends to all other prims
LINK_ALL_CHILDREN	-3	sends to all children, (everything but the root)
LINK_THIS	-4	sends to the prim the script is in
</pre>

*警告
#A script can hear its own linked messages if link targets the prim it is in[3]. This creates the possibility of an infinite loop (a bad thing); be very careful about how messages are handled and passed along.
#Messages sent via llMessageLinked to a script that is sleeping, delayed, or lagged, are queued until the end of the delay. The event queue can hold 64 events.
##If an event is received and the queue is full the event is silently dropped.
##Avoid sending link_messages to large numbers of scripts simultaneously as it can cause lag spike. This most often happens when using the multi-prim LINK_* flags and can cause script execution to slow or halts.
##Avoid sending link_messages to a target faster than they can be handled. Doing so risks filling the event queue and subsequent messages being silently discarded.
#When a script state changes, all pending events are deleted, including queued link_messages.
#If link is an invalid link number then the function silently fails.
#If str & id exceed the available memory of a script that catches the resulting link_message event, that script will crash with a Stack-Heap Collision.

*例子

<pre>
default
{
    // assumptions  // object name: LSLWiki // script name: _lslwiki
    state_entry()
    {
        llMessageLinked(LINK_THIS, 0, llGetScriptName(), "");
    }
 
    link_message(integer sender_num, integer num, string msg, key id)
    {
        llOwnerSay(msg);
        // the owner of object LSLWiki will hear
        // LSLWiki:_lslwiki
    }
}
</pre>

无穷循环，注意只用于测试功能。
<pre>
Message_Control(integer l, integer n) // Message_Total_Lack_Of_Control
{
    integer r = (++n); // Increment the value of n.
    llMessageLinked( l, r, "", ""); // Send the result to l
}
 
default
{
    state_entry()
    {
        Message_Control(LINK_SET, 0); // Tell all the scripts in the object that we have state_entered.
    }
    link_message(integer Sender, integer Number, string String, key Key) // This script is in the object too.
    {
        Message_Control(Sender, Number); // No filtering condition exists.
        llOwnerSay(((string)Number)); // Look at all the pretty numbers!
    }
}
</pre>

有用的代码片段
<pre>
default
{
    // 在debug窗口输出，捕获link message事件
    link_message(integer sender_num, integer num, string msg, key id)
    {
        llSay(DEBUG_CHANNEL, llList2CSV([sender_num, num, msg, id]));
    }
}
// This is just an example script, you shouldn't handle link message within single script this way.
 
default
{
    // 演示如何传输多个参数，放到list中!
    state_entry()
    {
        list my_list = [1, 2.0, "a string", <1, 2, 3>, <1, 2, 3, 4>, llGetOwner()];
        string list_parameter = llDumpList2String(my_list, "|");    // Convert the list to a string
        llMessageLinked(LINK_THIS, 0, list_parameter, "");//发送到物体中所有的脚本
    }
 
    link_message(integer sender_num, integer num, string list_argument, key id)
    {
        list re_list = llParseString2List(list_argument, ["|"], []);    // Parse the string back to a list
    }
}
</pre>