Create a new session id.
The session id is a secure random number by SecureRandom if possible, otherwise an SHA512 hash based upon the time, a random number, and a constant string. This routine is used internally for automatically generated session ids.
Creates a regular expression to match IPv4 addresses
Check that a method is callable via dRuby.
obj is the object we want to invoke the method on. msg_id is the method name, as a Symbol.
If the method is an insecure method (see insecure_method?) a SecurityError is thrown. If the method is private or undefined, a NameError is thrown.