---
title: NSSystemClockDidChange
framework: foundation
role: symbol
role_heading: Type Property
path: foundation/nsnotification/name-swift.struct/nssystemclockdidchange
---

# NSSystemClockDidChange

A notification posted whenever the system clock is changed.

## Declaration

```swift
static let NSSystemClockDidChange: NSNotification.Name
```

## Discussion

Discussion This can be initiated by a call to settimeofday(_:_:) or the user changing values in the Date and Time Preference panel. The notification object is null. This notification does not contain a userInfo dictionary.