mongoc_collection_set_write_concern man page
mongoc_collection_set_write_concern — mongoc_collection_set_write_concern()
void mongoc_collection_set_write_concern ( mongoc_collection_t *collection, const mongoc_write_concern_t *write_concern);
collection: A mongoc_collection_t.
write_concern: A mongoc_write_concern_t.
Sets the write concern to use for operations on collection.
The default write concern is MONGOC_WRITE_CONCERN_W_DEFAULT: the driver blocks awaiting basic acknowledgment of write operations from MongoDB. This is the correct write concern for the great majority of applications.
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