1e41f4b71Sopenharmony_ci# loop.h
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4e41f4b71Sopenharmony_ci## Overview
5e41f4b71Sopenharmony_ci
6e41f4b71Sopenharmony_ciThe **loop.h** file declares the loop interfaces in C.
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8e41f4b71Sopenharmony_ci**System capability**: SystemCapability.Resourceschedule.Ffrt.Core
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10e41f4b71Sopenharmony_ci**Since**: 12
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12e41f4b71Sopenharmony_ci**Related module**: [FFRT](_f_f_r_t.md)
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15e41f4b71Sopenharmony_ci## Summary
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18e41f4b71Sopenharmony_ci### Types
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20e41f4b71Sopenharmony_ci| Name| Description| 
21e41f4b71Sopenharmony_ci| -------- | -------- |
22e41f4b71Sopenharmony_ci|  typedef void\*  **ffrt_loop_t** |  | 
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25e41f4b71Sopenharmony_ci### Functions
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27e41f4b71Sopenharmony_ci| Name| Description| 
28e41f4b71Sopenharmony_ci| -------- | -------- |
29e41f4b71Sopenharmony_ci| FFRT_C_API ffrt_loop_t [ffrt_loop_create](_f_f_r_t.md#ffrt_loop_create) ([ffrt_queue_t](_f_f_r_t.md) queue) | Creates a loop. | 
30e41f4b71Sopenharmony_ci| FFRT_C_API int [ffrt_loop_destory](_f_f_r_t.md#ffrt_loop_destory) (ffrt_loop_t loop) | Destroys a loop. | 
31e41f4b71Sopenharmony_ci| FFRT_C_API int [ffrt_loop_run](_f_f_r_t.md#ffrt_loop_run) (ffrt_loop_t loop) | Runs a loop. | 
32e41f4b71Sopenharmony_ci| FFRT_C_API void [ffrt_loop_stop](_f_f_r_t.md#ffrt_loop_stop) (ffrt_loop_t loop) | Stops a loop. | 
33e41f4b71Sopenharmony_ci| FFRT_C_API int [ffrt_loop_epoll_ctl](_f_f_r_t.md#ffrt_loop_epoll_ctl) (ffrt_loop_t loop, int op, int fd, uint32_t events, void\* data, [ffrt_poller_cb](_f_f_r_t.md#ffrt_poller_cb) cb) | Manages listening events on a loop. | 
34e41f4b71Sopenharmony_ci| FFRT_C_API [ffrt_timer_t](_f_f_r_t.md#ffrt_timer_t)[ffrt_loop_timer_start](_f_f_r_t.md#ffrt_loop_timer_start) (ffrt_loop_t loop, uint64_t timeout, void\* data, [ffrt_timer_cb](_f_f_r_t.md#ffrt_timer_cb) cb, bool repeat) | Starts the timer on a loop. | 
35e41f4b71Sopenharmony_ci| FFRT_C_API int [ffrt_loop_timer_stop](_f_f_r_t.md#ffrt_loop_timer_stop) (ffrt_loop_t loop, [ffrt_timer_t](_f_f_r_t.md#ffrt_timer_t) handle) | Stops the timer on a loop. | 
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