How to listen to only one channel with Spy

I’m trying to monitor the two parties of a call separately. with the option ‘o’ ( I can easily listen to just the person that was calling in.

That allows to monitor the caller, however I’d like to monitor/listen to my operator only and it doesn’t seem that there is an option as counter part of ‘o’.

In fact in the code you can easily see that if ‘o’ is set, the spy mode is READ (, otherwise set to both.
To achieve what I’d like (listening just to my operator), I believe there should be also another option, which is using the WRITE operation: doxygen.asterisk.orgg/asterisk1.8/audiohook_8h.html#34d75d3d5e7418b6a772e3d522a168998254a5b3fc181d3fe3f2af892010b586 (this is a link but it is spelled wrong because as a new user I can just post 2 links, orgg instead of org)

Do you have any idea of possible alternatives or if hunch is correct?