I added a topic.
But I occur a strange problem.
There is not a topic publish.
But orb_check always set update flag true.
Any one occur this?
When you advertise topic (orb_advertise or orb_advertise_multi) it publishes the initial data (there is a pointer to the initial data to be published as second argument of these functions).
So orb_check checks whether a topic has been published and return true as should.
According to orb_check documentation:
this call will continue to return true until orb_copy is called using the same handle.
That is, you probably do not call orb_copy after orb_check.