1# queue.h 2 3 4## Overview 5 6The **queue.h** file declares the queue interfaces in C. 7 8**Since**: 10 9 10**Related module**: [FFRT](_f_f_r_t.md) 11 12 13## Summary 14 15 16### Types 17 18| Name| Description| 19| -------- | -------- | 20| typedef void \* [ffrt_queue_t](_f_f_r_t.md) | Defines a queue handle. | 21 22 23### Enums 24 25| Name| Description| 26| -------- | -------- | 27| [ffrt_queue_type_t](_f_f_r_t.md#ffrt_queue_type_t) { [ffrt_queue_serial](_f_f_r_t.md), **ffrt_queue_max** } | Enumerates the queue types. | 28 29 30### Functions 31 32| Name| Description| 33| -------- | -------- | 34| FFRT_C_API int [ffrt_queue_attr_init](_f_f_r_t.md#ffrt_queue_attr_init) ([ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr) | Initializes a queue attribute. | 35| FFRT_C_API void [ffrt_queue_attr_destroy](_f_f_r_t.md#ffrt_queue_attr_destroy) ([ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr) | Destroys a queue attribute. | 36| FFRT_C_API void [ffrt_queue_attr_set_qos](_f_f_r_t.md#ffrt_queue_attr_set_qos) ([ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr, [ffrt_qos_t](_f_f_r_t.md) qos) | Sets the queue QoS. | 37| FFRT_C_API [ffrt_qos_t](_f_f_r_t.md)[ffrt_queue_attr_get_qos](_f_f_r_t.md#ffrt_queue_attr_get_qos) (const [ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr) | Obtains the queue QoS. | 38| FFRT_C_API void [ffrt_queue_attr_set_timeout](_f_f_r_t.md#ffrt_queue_attr_set_timeout) ([ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr, uint64_t timeout_us) | Sets the queue timeout. | 39| FFRT_C_API uint64_t [ffrt_queue_attr_get_timeout](_f_f_r_t.md#ffrt_queue_attr_get_timeout) (const [ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr) | Obtains the queue timeout. | 40| FFRT_C_API void [ffrt_queue_attr_set_callback](_f_f_r_t.md#ffrt_queue_attr_set_callback) ([ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr, [ffrt_function_header_t](ffrt__function__header__t.md) \*f) | Sets a callback that is invoked when a queue task times out. | 41| FFRT_C_API [ffrt_function_header_t](ffrt__function__header__t.md) \* [ffrt_queue_attr_get_callback](_f_f_r_t.md#ffrt_queue_attr_get_callback) (const [ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr) | Obtains the callback that is invoked when a queue task times out. | 42| FFRT_C_API [ffrt_queue_t](_f_f_r_t.md)[ffrt_queue_create](_f_f_r_t.md#ffrt_queue_create) ([ffrt_queue_type_t](_f_f_r_t.md#ffrt_queue_type_t) type, const char \*name, const [ffrt_queue_attr_t](ffrt__queue__attr__t.md) \*attr) | Creates a queue. | 43| FFRT_C_API void [ffrt_queue_destroy](_f_f_r_t.md#ffrt_queue_destroy) ([ffrt_queue_t](_f_f_r_t.md) queue) | Destroys a queue. | 44| FFRT_C_API void [ffrt_queue_submit](_f_f_r_t.md#ffrt_queue_submit) ([ffrt_queue_t](_f_f_r_t.md) queue, [ffrt_function_header_t](ffrt__function__header__t.md) \*f, const [ffrt_task_attr_t](ffrt__task__attr__t.md) \*attr) | Submits a task to a queue. | 45| FFRT_C_API [ffrt_task_handle_t](_f_f_r_t.md)[ffrt_queue_submit_h](_f_f_r_t.md#ffrt_queue_submit_h) ([ffrt_queue_t](_f_f_r_t.md) queue, [ffrt_function_header_t](ffrt__function__header__t.md) \*f, const [ffrt_task_attr_t](ffrt__task__attr__t.md) \*attr) | Submits a task to a queue, and obtains a task handle. | 46| FFRT_C_API void [ffrt_queue_wait](_f_f_r_t.md#ffrt_queue_wait) ([ffrt_task_handle_t](_f_f_r_t.md) handle) | Waits until a task in the queue is complete. | 47| FFRT_C_API int [ffrt_queue_cancel](_f_f_r_t.md#ffrt_queue_cancel) ([ffrt_task_handle_t](_f_f_r_t.md) handle) | Cancels a task in the queue. | 48