> ## Documentation Index
> Fetch the complete documentation index at: https://instro.nominal.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Publishers: publish shared

```python publish_shared.py theme={null}
"""Example: Publishers: publish shared."""

from instro.lib.publishers import FilePublisher, SharedPublisher
from instro.psu import InstroPSU
from instro.psu.drivers import SimulatedPSU

PRIMARY_VISA_RESOURCE = "TCPIP0::127.0.0.1::5025::SOCKET"
SECONDARY_VISA_RESOURCE = "TCPIP0::127.0.0.1::5026::SOCKET"

file_publisher = FilePublisher(directory="./captures", format="avro", custom_file_name="shared_publishers")
shared_publisher = SharedPublisher(file_publisher)

primary_psu = InstroPSU(
    name="primaryPSU",
    driver=SimulatedPSU(PRIMARY_VISA_RESOURCE),
    num_channels=2,
    publishers=[shared_publisher],
)
secondary_psu = InstroPSU(
    name="secondaryPSU",
    driver=SimulatedPSU(SECONDARY_VISA_RESOURCE),
    num_channels=2,
    publishers=[shared_publisher.clone()],
)

try:
    primary_psu.open()
    secondary_psu.open()

    primary_psu.set_voltage(1.0, channel=1)
    primary_psu.get_voltage(channel=1)

    secondary_psu.set_voltage(2.0, channel=1)
    secondary_psu.get_voltage(channel=1)
finally:
    primary_psu.close()
    # The underlying FilePublisher stays open until the final shared handle closes.
    secondary_psu.close()
```