# hs.usb.watcher

Watch for USB device connection/disconnection events

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# API Overview

Constructors - API calls which return an object, typically one that offers API methods

• new

Methods - API calls which can only be made on an object returned by a constructor

• start
• stop

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# API Documentation

# Constructors

# new

| | | | --------------------------------------------|-------------------------------------------------------------------------------------| | Signature | hs.usb.watcher.new(fn) -> watcher | | Type | Constructor | | Description | Creates a new watcher for USB device events | | Parameters |

• fn - A function that will be called when a USB device is inserted or removed. The function should accept a single parameter, which is a table containing the following keys: eventType - A string containing either "added" or "removed" depending on whether the USB device was connected or disconnected productName - A string containing the name of the device vendorName - A string containing the name of the device vendor vendorID - A number containing the Vendor ID of the device productID - A number containing the Product ID of the device

| | Returns |

• A hs.usb.watcher object

| | Notes | None | | Examples | None | | Source | extensions/usb/libusb_watcher.m line 177 |

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# Methods

# start

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# stop

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