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# zx_timer_create
## SUMMARY
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Create a timer.
## DECLARATION
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```c
#include <zircon/syscalls.h>
zx_status_t zx_timer_create(uint32_t options,
zx_clock_t clock_id,
zx_handle_t* out);
```
## DESCRIPTION
`zx_timer_create()` creates a timer, an object that can signal
when a specified point in time has been reached. The only valid
*clock_id* is **ZX_CLOCK_MONOTONIC**.
The *options* value specifies the coalescing behavior, which
controls whether the system can fire the time earlier or later
depending on other pending timers.
The possible values are:
+ **ZX_TIMER_SLACK_CENTER**
+ **ZX_TIMER_SLACK_EARLY**
+ **ZX_TIMER_SLACK_LATE**
Passing 0 in options is equivalent to **ZX_TIMER_SLACK_CENTER**.
See [timer slack](/docs/concepts/kernel/timer_slack.md) for more information.
The returned handle has the **ZX_RIGHT_DUPLICATE**, **ZX_RIGHT_TRANSFER**,
**ZX_RIGHT_WRITE**, **ZX_RIGHT_SIGNAL**, **ZX_RIGHT_WAIT**, and
**ZX_RIGHT_INSPECT** rights.
## RIGHTS
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Caller job policy must allow **ZX_POL_NEW_TIMER**.
## RETURN VALUE
`zx_timer_create()` returns **ZX_OK** on success. In the event
of failure, a negative error value is returned.
## ERRORS
**ZX_ERR_INVALID_ARGS** *out* is an invalid pointer or NULL or
*options* is not one of the **ZX_TIMER_SLACK** values or *clock_id* is
any value other than **ZX_CLOCK_MONOTONIC**.
**ZX_ERR_NO_MEMORY** Failure due to lack of memory.
There is no good way for userspace to handle this (unlikely) error.
In a future build this error will no longer occur.
## SEE ALSO
- [`zx_deadline_after()`]
- [`zx_handle_close()`]
- [`zx_timer_cancel()`]
- [`zx_timer_set()`]
<!-- References updated by update-docs-from-fidl, do not edit. -->
[`zx_deadline_after()`]: deadline_after.md
[`zx_handle_close()`]: handle_close.md
[`zx_timer_cancel()`]: timer_cancel.md
[`zx_timer_set()`]: timer_set.md