Specifications

Remember you can invoke functions remotely
Writing modular code is always a good idea. As an added bonus, if you are able to break your overall
script into multiple function definitions, you can remotely invoke the individual routines. This can
help in determining where any problem lies.
Be careful using multicast RPC invocation
Realize that if you multicast an RPC call to function “foo”, all nodes in that multicast group that have
a foo() function will execute theirs. To put it another way, give your SNAPpy functions distinct and
meaningful names.
If all nodes hear the question at the same time, they will all answer at the same time
If you have more than a few nodes, you will need to coordinate their responses (using a SNAPpy
script) if you poll them via a multicast RPC call.
If you want to call a built-in function by name, the called node needs a script loaded, even if it is
empty
SNAP Nodes without scripts loaded only support function calls by number. The “name lookup table”
that lets nodes support “call by name” is part of what gets sent with each SNAPpy Image.
When Portal invokes built-in functions for you (from the GUI), it automatically converts function
names to function numbers. Standalone SNAP nodes don’t know how to do this conversion.
So, if you don’t have any real script to put into a node that you want to control from something
besides Portal, upload an empty one.
SNAP Reference Manual Document Number 600-0007K Page 91 of 202