Espressif ESP32-S2 Programming Manual page 629

Chapter 2. API Reference
Return
• ESP_OK success
• ESP_ERR_INVALID_STATE mDNS is not running
• ESP_ERR_NO_MEM memory error
• ESP_ERR_INVALID_ARG timeout was not given
Parameters
• name: service instance or host name (NULL for PTR queries)
• service_type: service type (_http, _arduino, _ftp etc.) (NULL for host queries)
• proto: service protocol (_tcp, _udp, etc.) (NULL for host queries)
• type: type of query (MDNS_TYPE_*)
• timeout: time in milliseconds to wait for answers.
• max_results: maximum results to be collected
• results: pointer to the results of the query results must be freed using mdns_query_results_free
below
void mdns_query_results_free(mdns_result_t
Free query results.
Parameters
• results: linked list of results to be freed
esp_err_t mdns_query_ptr(const char *service_type, const char *proto, uint32_t timeout, size_t
Query mDNS for service.
Return
• ESP_OK success
• ESP_ERR_INVALID_STATE mDNS is not running
• ESP_ERR_NO_MEM memory error
• ESP_ERR_INVALID_ARG parameter error
Parameters
• service_type: service type (_http, _arduino, _ftp etc.)
• proto: service protocol (_tcp, _udp, etc.)
• timeout: time in milliseconds to wait for answer.
• max_results: maximum results to be collected
• results: pointer to the results of the query
esp_err_t mdns_query_srv(const char *instance_name, const char *service_type, const char
Query mDNS for SRV record.
Return
• ESP_OK success
• ESP_ERR_INVALID_STATE mDNS is not running
• ESP_ERR_NO_MEM memory error
• ESP_ERR_INVALID_ARG parameter error
Parameters
• instance_name: service instance name
• service_type: service type (_http, _arduino, _ftp etc.)
• proto: service protocol (_tcp, _udp, etc.)
• timeout: time in milliseconds to wait for answer.
• result: pointer to the result of the query
esp_err_t mdns_query_txt(const char *instance_name, const char *service_type, const char
Query mDNS for TXT record.
Return
• ESP_OK success
• ESP_ERR_INVALID_STATE mDNS is not running
• ESP_ERR_NO_MEM memory error
• ESP_ERR_INVALID_ARG parameter error
Parameters
Espressif Systems
*results)
max_results, mdns_result_t
*proto, uint32_t timeout, mdns_result_t
*proto, uint32_t timeout, mdns_result_t
618
Submit Document Feedback
**results)
**result)
**result)
Release v4.4