System Library Files

Good afternoon,

Is there is an actual file location where the system library .py files are stored?

When you say “the system library”, are you literally referring to the built-in system functions (system.tag.writeBlocking, system.db.runNamedQuery, etc)? They wrapped up in the various modules and JARs included in an installation, which means they’re not really accessible on the file system.

If you’re talking about the various Python libraries that are included in an instillation (,, etc), they’re located at %gatewayInstallDirectory%/user-lib-pylib

Someone did make a library of mock functions, but it hasn’t been updated in a while, so they may be a little outdated.


Yep, the built-in system functions. We were wondering if there was any way to look at them directly pretty much for the same reason as thecesrom in that link Rumin posted - which is very helpful! Thank you.

It’s worth noting here that the system.* namespace is populated with java classes and methods constructed to work in the jython interpreter. There’s no python to “look at”. This is documented in the Ignition SDK.

Quite right, as Paul already mentioned. That’s why I didn’t mention python in my last post. I was actually going to check around in the Ignition java docs to see if I could find anything, but the link Rumin posted works.

Currently the mock library does not contain the full list of modules and functions as the actual system.* namespace, only the function calls that I’ve used on my projects, and new things are added as needed.

If you’d like to contribute, just let me know.