1e41f4b71Sopenharmony_ci# HiTraceId
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4e41f4b71Sopenharmony_ci## Overview
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6e41f4b71Sopenharmony_ciDefines a struct for **HiTraceId**.
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8e41f4b71Sopenharmony_ci**System capability**: SystemCapability.HiviewDFX.HiTrace
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10e41f4b71Sopenharmony_ci**Since**: 12
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12e41f4b71Sopenharmony_ci**Related module**: [Hitrace](_hitrace.md)
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15e41f4b71Sopenharmony_ci## Summary
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18e41f4b71Sopenharmony_ci### Member Variables
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20e41f4b71Sopenharmony_ciA little-endian **HiTraceId** consists of the following fields in sequence: 
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22e41f4b71Sopenharmony_ci| Field| Number of Bits| Description| 
23e41f4b71Sopenharmony_ci| -------- | -------- | -------- |
24e41f4b71Sopenharmony_ci| uint64_t [valid](_hitrace.md#valid) | 1 | Whether **HiTraceId** is valid. | 
25e41f4b71Sopenharmony_ci| uint64_t [ver](_hitrace.md#ver) | 3 | Version number of **HiTraceId**. | 
26e41f4b71Sopenharmony_ci| uint64_t [chainId](_hitrace.md#chainid) | 60 | Chain ID of **HiTraceId**. | 
27e41f4b71Sopenharmony_ci| uint64_t [flags](_hitrace.md#flags) | 12 | Flag of **HiTraceId**. | 
28e41f4b71Sopenharmony_ci| uint64_t [spanId](_hitrace.md#spanid) | 26 | Span ID of **HiTraceId**. | 
29e41f4b71Sopenharmony_ci| uint64_t [parentSpanId](_hitrace.md#parentspanid) | 26 | Parent span ID of **HiTraceId**. | 
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31e41f4b71Sopenharmony_ciA big-endian **HiTraceId** consists of the following fields in sequence: 
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33e41f4b71Sopenharmony_ci| Field| Number of Bits| Description| 
34e41f4b71Sopenharmony_ci| -------- | -------- | -------- |
35e41f4b71Sopenharmony_ci| uint64_t [chainId](_hitrace.md#chainid) | 60 | Chain ID of **HiTraceId**. | 
36e41f4b71Sopenharmony_ci| uint64_t [ver](_hitrace.md#ver) | 3 | Version number of **HiTraceId**. | 
37e41f4b71Sopenharmony_ci| uint64_t [valid](_hitrace.md#valid) | 1 | Whether **HiTraceId** is valid. | 
38e41f4b71Sopenharmony_ci| uint64_t [parentSpanId](_hitrace.md#parentspanid) | 26 | Parent span ID of **HiTraceId**. | 
39e41f4b71Sopenharmony_ci| uint64_t [spanId](_hitrace.md#spanid) | 26 | Span ID of **HiTraceId**. | 
40e41f4b71Sopenharmony_ci| uint64_t [flags](_hitrace.md#flags) | 12 | Flag of **HiTraceId**. | 
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