1# timer.h 2 3 4## Overview 5 6The **timer.h** file declares the timer interfaces in C. 7 8**File to include**: <ffrt/timer.h> 9 10**Library**: libffrt.z.so 11 12**System capability**: SystemCapability.Resourceschedule.Ffrt.Core 13 14**Since**: 12 15 16**Related module**: [FFRT](_f_f_r_t.md) 17 18 19## Summary 20 21 22### Functions 23 24| Name| Description| 25| -------- | -------- | 26| FFRT_C_API [ffrt_timer_t](_f_f_r_t.md#ffrt_timer_t) [ffrt_timer_start](_f_f_r_t.md#ffrt_timer_start) ([ffrt_qos_t](_f_f_r_t.md#ffrt_qos_t) qos, uint64_t timeout, void \*data, [ffrt_timer_cb](_f_f_r_t.md#ffrt_timer_cb) cb, bool repeat) | Starts the timer. | 27| FFRT_C_API int [ffrt_timer_stop](_f_f_r_t.md#ffrt_timer_stop) ([ffrt_qos_t](_f_f_r_t.md#ffrt_qos_t) qos, [ffrt_timer_t](_f_f_r_t.md#ffrt_timer_t) handle) | Stops the timer. | 28