Encoding a series of messages in JSON is similar to encoding a series of messages in any other set of encoding rules: iterate through the input data using a loop, using rtxMemReset to improve performance by reusing memory:

   /* initialize context, et c. */   
            
   for ( ; ; ) {
      /* initialize / populate message structure to be encoded */
      
      /* call MDEREnc_<messageType> (...); */
      
      /* call rtxMemReset when finished encoding: */
      rtxMemReset (pctxt);
   }