(PECL mongo >=1.1.0)
Mongo::getSlave — Returns the address being used by this for slaveOkay reads
This finds the address of the slave currently being used for reads. It is a read-only method: it does not change anything about the internal state of the object.
See the query section of this manual for information on distributing reads to slaves.
此函数没有参数。
The address of the slave this connection is using for reads.
This returns NULL if this is not connected to a replica set or not yet initialized.