---
title: CreatePMAssertion
framework: driverkit
role: symbol
role_heading: Instance Method
path: driverkit/ioservice/createpmassertion
---

# CreatePMAssertion

## Declaration

```occ
virtual kern_return_t CreatePMAssertion(uint32_t assertionBits, uint64_t *assertionID, bool synced);
```

## Parameters

- `assertionBits`: Bit masks including all the flavors that require to be asserted.
- `assertionID`: Pointer that will contain the unique identifier of the created power assertion.
- `synced`: Indicates if the assertion must prevent an imminent sleep transition. When set to true, and if a system sleep is irreversible, the call will return kIOReturnBusy, in which case the assertion is not created. Only kIOServicePMAssertionCPUBit is valid for assertionBits if sleepSafe is set to true.

## Return Value

Return Value kIOReturnSuccess on success. See IOReturn.h for error codes.

## Discussion

Discussion Create a power management assertion.