Synopsis:

       SMaddASRitem(vox_chan,vocab_id,user_id)

Arguments:

       vox_chan – The voice channel

       vocab_id – The Vocabulary ID to add to the set of ASR items that can be detaected on the channel.

       user_id -  The user defined ID for the vocabulary item

Description:   Each channel can have a set of Active Speech Recognition (ASR) vocabulary items defined for it that may  be recognised after a call to SMctlASR().     This function allows the vocab_id and associated user_id to be added to this set of ASR vocab items for the channel.        The set of vocabulary items on a channel will only become active upon the next call to SMctlASR().

Returns:  Returns 0 if successful or a negative error code.