LiveCode code that generates a UUID on OS X, Linux and Windows.

gistfile1.txt

function generateUUID
   local theError, theUUID
   
   switch the platform
      case "macos"
      case "linux"
         put shell("uuidgen") into theUUID
         put word 1 to -1 of theUUID into theUUID
         put the result into theError
         break
      case "win32"
         put format("set TypeLib = CreateObject(\"Scriptlet.TypeLib\")") into theVBScript
         put cr & "result = TypeLib.Guid" after theVBScript
         do theVBScript as "vbscript"
         put the result into theresult
         
         put word 1 to -1 of theresult into theressult
         
         if theresult begins with "{" then
            put char 2 to -2 of theresult into theUUID
         end if
         break
   end switch
   
   if theError is empty then
      return theUUID
   else
      return empty
   end if
end generateUUID