libudev Reference Manual: udev_queue

## udev_queue udev_queue — access to currently active events |

## Functions

struct udev_queue * | udev_queue_ref ()
struct udev_queue * | udev_queue_unref ()
struct udev * | udev_queue_get_udev ()
struct udev_queue * | udev_queue_new ()
int | udev_queue_get_udev_is_active ()
int | udev_queue_get_queue_is_empty ()
int | udev_queue_get_seqnum_is_finished ()
int | udev_queue_get_seqnum_sequence_is_finished ()
struct udev_list_entry * | udev_queue_get_queued_list_entry ()
unsigned long long int | udev_queue_get_kernel_seqnum ()
unsigned long long int | udev_queue_get_udev_seqnum ()
int | udev_queue_get_fd ()
int | udev_queue_flush ()

## Types and Values

struct | udev_queue

## Object Hierarchy

## Description

This exports the current state of the udev processing queue.

## Functions

### udev_queue_ref ()

    struct udev_queue *
    udev_queue_ref (struct udev_queue *udev_queue);

Take a reference of a udev queue context.

#### Parameters

udev_queue | udev queue context |

#### Returns

the same udev queue context.

### udev_queue_unref ()

    struct udev_queue *
    udev_queue_unref (struct udev_queue *udev_queue);

Drop a reference of a udev queue context. If the refcount reaches zero, the resources of the queue context will be released.

#### Parameters

udev_queue | udev queue context |

#### Returns

NULL

### udev_queue_get_udev ()

    struct udev *
    udev_queue_get_udev (struct udev_queue *udev_queue);

Retrieve the udev library context the queue context was created with.

#### Parameters

udev_queue | udev queue context |

#### Returns

the udev library context.

### udev_queue_new ()

    struct udev_queue *
    udev_queue_new (struct udev *udev);

The initial refcount is 1, and needs to be decremented to release the resources of the udev queue context.

#### Parameters

udev | udev library context |

#### Returns

the udev queue context, or NULL on error.

### udev_queue_get_udev_is_active ()

    int
    udev_queue_get_udev_is_active (struct udev_queue *udev_queue);

Check if udev is active on the system.

#### Parameters

udev_queue | udev queue context |

#### Returns

a flag indicating if udev is active.

### udev_queue_get_queue_is_empty ()

    int
    udev_queue_get_queue_is_empty (struct udev_queue *udev_queue);

Check if udev is currently processing any events.

#### Parameters

udev_queue | udev queue context |

#### Returns

a flag indicating if udev is currently handling events.

### udev_queue_get_seqnum_is_finished ()

    int
    udev_queue_get_seqnum_is_finished (struct udev_queue *udev_queue,
                                       unsigned long long int seqnum);

This function is deprecated, it just returns the result of `udev_queue_get_queue_is_empty()`.

#### Parameters

udev_queue | udev queue context |
seqnum | sequence number |

#### Returns

a flag indicating if udev is currently handling events.

### udev_queue_get_seqnum_sequence_is_finished ()

    int
    udev_queue_get_seqnum_sequence_is_finished
                                   (struct udev_queue *udev_queue,
                                    unsigned long long int start,
                                    unsigned long long int end);

This function is deprecated, it just returns the result of `udev_queue_get_queue_is_empty()`.

#### Parameters

udev_queue | udev queue context |
start | first event sequence number |
end | last event sequence number |

#### Returns

a flag indicating if udev is currently handling events.

### udev_queue_get_queued_list_entry ()

    struct udev_list_entry *
    udev_queue_get_queued_list_entry (struct udev_queue *udev_queue);

This function is deprecated.

#### Parameters

udev_queue | udev queue context |

#### Returns

NULL.

### udev_queue_get_kernel_seqnum ()

    unsigned long long int
    udev_queue_get_kernel_seqnum (struct udev_queue *udev_queue);

This function is deprecated.

#### Parameters

udev_queue | udev queue context |

#### Returns

0.

### udev_queue_get_udev_seqnum ()

    unsigned long long int
    udev_queue_get_udev_seqnum (struct udev_queue *udev_queue);

This function is deprecated.

#### Parameters

udev_queue | udev queue context |

#### Returns

0.

### udev_queue_get_fd ()

    int
    udev_queue_get_fd (struct udev_queue *udev_queue);

#### Parameters

udev_queue | udev queue context |

#### Returns

a file descriptor to watch for a queue to become empty.

### udev_queue_flush ()

    int
    udev_queue_flush (struct udev_queue *udev_queue);

#### Parameters

udev_queue | udev queue context |

#### Returns

the result of clearing the watch for queue changes.

## Types and Values

### struct udev_queue

    struct udev_queue;

Opaque object representing the current event queue in the udev daemon.