Tell me how to acquire locking in PRPC?

Process Commander has several locking mechanisms:
=> You can lock a RuleSet version with passwords, preventing any changes to the rules associated with that RuleSet or version.
=> A requestor may acquire temporary exclusive access to an instance, preventing other requestors from updating or deleting it.
=> You can lock an application rule (Rule-Application rule type) with a password, preventing others from changing that rule instance until they enter the password.

Obj-Refresh-and-Lock   Open an instance and acquire a lock.
Page-Unlock            Release a lock held after Commit.