io\_uring\_prep\_timeout\_update(3) liburing Manual io\_uring\_prep\_timeout\_update(3)

# [NAME](#NAME)

io\_uring\_prep\_timeout\_update - prepare a request to update an existing timeout

# [SYNOPSIS](#SYNOPSIS)

```
#include <liburing.h>
```

```
void io_uring_prep_timeout_update(struct io_uring_sqe *sqe,
                                  const struct __kernel_timespec *ts,
                                  __u64 user_data,
                                  unsigned flags);
```

```
void io_uring_prep_timeout_remove(struct io_uring_sqe *sqe,
                                  __u64 user_data,
                                  unsigned flags);
```

# [DESCRIPTION](#DESCRIPTION)

These functions modify or cancel an existing timeout request. The submission queue entry *sqe* is setup to arm a timeout update or removal specified by *user\_data* and with modifier flags given by *flags*. Additionally, the update request includes a *ts* structure, which contains new timeout information.

For an update request, the *flags* member may contain a bitmask of the following values:

[**IORING\_TIMEOUT\_ABS**](#IORING_TIMEOUT_ABS)

The value specified in *ts* is an absolute value rather than a relative one.

The timeout remove command does not currently accept any flags.

# [RETURN VALUE](#RETURN_VALUE)

None

# [ERRORS](#ERRORS)

These are the errors that are reported in the CQE *res* field. On success, **0** is returned.

[**-ENOENT**](#ENOENT)

The timeout identified by *user\_data* could not be found. It may be invalid, or triggered before the update or removal request was processed.

[**-EALREADY**](#EALREADY)

The timeout identified by *user\_data* is already firing and cannot be canceled.

[**-EINVAL**](#EINVAL)

One of the fields set in the SQE was invalid. For example, two clocksources were given, or the specified timeout seconds or nanoseconds were &lt; 0.

[**-EFAULT**](#EFAULT)

io\_uring was unable to access the data specified by *ts*.

# [NOTES](#NOTES)

As with any request that passes in data in a struct, that data must remain valid until the request has been successfully submitted. It need not remain valid until completion. Once a request has been submitted, the in-kernel state is stable. Very early kernels (5.4 and earlier) required state to be stable until the completion occurred. Applications can test for this behavior by inspecting the **IORING\_FEAT\_SUBMIT\_STABLE** flag passed back from [**io\_uring\_queue\_init\_params**(3)](/man/os/liburing/io_uring_queue_init_params.3).

# [SEE ALSO](#SEE_ALSO)

[**io\_uring\_get\_sqe**(3)](/man/os/liburing/io_uring_get_sqe.3), [**io\_uring\_submit**(3)](/man/os/liburing/io_uring_submit.3), [**io\_uring\_prep\_timeout**(3)](/man/os/liburing/io_uring_prep_timeout.3)

March 12, 2022 liburing-2.2

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Document: io_uring_prep_timeout_update(3) from liburing 2.15-r4 (Chainguard OS)
Source: https://github.com/axboe/liburing.git