mongoc_apm_callbacks_t man page
mongoc_apm_callbacks_t — mongoc_apm_callbacks_t
Used to receive notification of events, such as when a MongoDB command begins, succeeds, or fails.
Create a mongoc_apm_callbacks_t with mongoc_apm_callbacks_new, set callbacks on it, then pass it to mongoc_client_set_apm_callbacks or mongoc_client_pool_set_apm_callbacks.
Introduction to Application Performance Monitoring
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