From InWorldz Wiki
PURPOSE: Sends a message through a chat channel.
TWO PARAMETERS: channel: an integer value of 0, positive or negative range. message: the information sent.
EXAMPLE: llSay (0, "Greetings, visitor!" );
IMPORTANT NOTES: * Only string information can be chatted. All other information must be converted to a string. * Messages chatted are "heard" through the use of the llListen() function and the listen() event. * A script cannot listen() to itself. Use llMessageLinked() instead. * llSay() can chat between objects, unlike llMessageLinked() which can only communicate within the same object. * See CHANNELS for information on channel usage.
llSay(0,"This will be shown in main chat and can be read by anyone."); llSay(0,"This is an example of string conversion: " + (string) numericVariable + "."); llSay(23,"This will only be heard by other scripts listening on channel 23 but not by avatars."); llSay(-5,"This will only be heard by other scripts listening on channel -5, but cannot be avatar-originated.");
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