---
title: attemptCommand
framework: kernel
role: pseudoSymbol
path: kernel/iocommandgate/1811141-attemptcommand
---

# attemptCommand

Single thread a command with the target work-loop.

## Declaration

```occ
virtual IOReturn attemptCommand(
 void *arg0 = 0,
 void *arg1 = 0, 
 void *arg2 = 0,
 void *arg3 = 0); 
```

## Parameters

- `arg0`: Parameter for action of command gate, defaults to 0.
- `arg1`: Parameter for action of command gate, defaults to 0.
- `arg2`: Parameter for action of command gate, defaults to 0.
- `arg3`: Parameter for action of command gate, defaults to 0.

## Return Value

Return Value kIOReturnSuccess if successful. kIOReturnNotPermitted if this event source is currently disabled, kIOReturnNoResources if no action available, kIOReturnCannotLock if lock attempt fails.

## Overview

Overview Client function that causes the current action to be called in a single threaded manner. When the executing on a client's thread attemptCommand will fail if the work-loop's gate is closed.

## See Also

### Miscellaneous

- [attemptAction](kernel/iocommandgate/1811105-attemptaction.md)
- [commandGate](kernel/iocommandgate/1811293-commandgate.md)
- [commandSleep(void *, AbsoluteTime, UInt32)](kernel/iocommandgate/1811482-commandsleep.md)
- [commandSleep(void *, UInt32)](kernel/iocommandgate/1811498-commandsleep.md)
- [commandWakeup](kernel/iocommandgate/1811517-commandwakeup.md)
- [disable](kernel/iocommandgate/1811531-disable.md)
- [enable](kernel/iocommandgate/1811547-enable.md)
- [init](kernel/iocommandgate/1811560-init.md)
- [runAction](kernel/iocommandgate/1811576-runaction.md)
- [runCommand](kernel/iocommandgate/1811585-runcommand.md)