---
title: handleIsOpen
framework: kernel
role: pseudoSymbol
path: kernel/iohideventservice/1812770-handleisopen
---

# handleIsOpen

Query whether a client has an open on the interface.

## Declaration

```occ
virtual bool handleIsOpen(
 const IOService *client) const; 
```

## Return Value

Return Value true if the specified client, or any client if none (0) is specified, presently has an open on this object.

## Overview

Overview This method is always called by IOService with the arbitration lock held. Subclasses should not override this method.

## See Also

### Miscellaneous

- [dispatchDigitizerEvent](kernel/iohideventservice/1812711-dispatchdigitizerevent.md)
- [dispatchDigitizerEventWithPolarOrientation](kernel/iohideventservice/1812728-dispatchdigitizereventwithpolaro.md)
- [dispatchDigitizerEventWithTiltOrientation](kernel/iohideventservice/1812735-dispatchdigitizereventwithtiltor.md)
- [dispatchMultiAxisPointerEvent](kernel/iohideventservice/1812745-dispatchmultiaxispointerevent.md)
- [handleClose](kernel/iohideventservice/1812757-handleclose.md)
- [handleOpen](kernel/iohideventservice/1812786-handleopen.md)
- [handleStart](kernel/iohideventservice/1812803-handlestart.md)
- [handleStop](kernel/iohideventservice/1812816-handlestop.md)