Read Note Card Configuration

Learn how to read configuration files with Linden Scripting Language (LSL) in Second Life (SL). After viewing this tutorial, you will be able to:

• Create a script
• Read each line of a note card
• Skip over comments
• Skip blank lines
• Notify the owner of the lines with unknown settings
  • Unknown setting name
  • Missing delimiter (equal sign)
• Notify the owner of missing configuration note card
• Detect when the notecard has been changed
• Offer case-insensitive settings
• Trim white-space from name/value settings
• Initialize with default values
• Detect that the name of the configuration file is a notecard
• Detect that you have reached the end of the file

1. DOWNLOAD How to read configuration information from a notecard

# this is a file to configure your application
# blank lines are ignored as well as lines
# proceeded with a "#" sign.
Name = Dedric Mauriac
Favorite Color = Blue

<lsl> string configurationNotecardName = "Application.Config"; key notecardQueryId; integer line;

string AvatarName; string FavoriteColor;

init() { // reset configuration values to default

   AvatarName = "Unknown";
   FavoriteColor = "None";

// make sure the file exists and is a notecard

   if(llGetInventoryType(configurationNotecardName) != INVENTORY_NOTECARD)
   {
   //  notify owner of missing file
       llOwnerSay("Missing inventory notecard: " + configurationNotecardName);
   //  don't do anything else
       return;
   }

// initialize to start reading from first line (which is 0)

   line = 0;
   notecardQueryId = llGetNotecardLine(configurationNotecardName, line);

}

processConfiguration(string data) { // if we are at the end of the file

   if(data == EOF)
   {
   //  notify the owner
       llOwnerSay("We are done reading the configuration");

   //  notify what was read
       llOwnerSay("The avatar name is: " + AvatarName);
       llOwnerSay("The favorite color is: " + FavoriteColor);

   //  do not do anything else
       return;
   }

// if we are not working with a blank line

   if(data != "")
   {
   //  if the line does not begin with a comment
       if(llSubStringIndex(data, "#") != 0)
       {
       //  find first equal sign
           integer i = llSubStringIndex(data, "=");

       //  if line contains equal sign
           if(i != -1)
           {
           //  get name of name/value pair
               string name = llGetSubString(data, 0, i - 1);

           //  get value of name/value pair
               string value = llGetSubString(data, i + 1, -1);

           //  trim name
               list temp = llParseString2List(name, [" "], []);
               name = llDumpList2String(temp, " ");

           //  make name lowercase (case insensitive)
               name = llToLower(name);

           //  trim value
               temp = llParseString2List(value, [" "], []);
               value = llDumpList2String(temp, " ");

           //  name
               if(name == "name")
                   AvatarName = value;

           //  color
               else if(name == "favorite color")
                   FavoriteColor = value;

           //  unknown name
               else
                   llOwnerSay("Unknown configuration value: " + name + " on line " + (string)line);

           }
       //  line does not contain equal sign
           else
           {
               llOwnerSay("Configuration could not be read on line " + (string)line);
           }
       }
   }

// read the next line

   notecardQueryId = llGetNotecardLine(configurationNotecardName, ++line);

}

default {

   on_rez(integer start_param)
   {
       init();
   }

   changed(integer change)
   {
       if(change & (CHANGED_OWNER | CHANGED_INVENTORY))
           init();
   }

   state_entry()
   {
       init();
   }

   dataserver(key request_id, string data)
   {
       if(request_id == notecardQueryId)
           processConfiguration(data);
   }

} </lsl>