# C-Language Symbols ## Topics ### C Network Structures [`struct nw_connection_group_state_t`](/documentation/Network/nw_connection_group_state_t) States that indicate whether you can use a connection group to send and receive messages. [`struct nw_browser_state_t`](/documentation/Network/nw_browser_state_t) States indicating whether a browser is able to discover services. [`struct nw_connection_state_t`](/documentation/Network/nw_connection_state_t) States indicating whether a connection can be used to send and receive data. [`struct nw_data_transfer_report_state_t`](/documentation/Network/nw_data_transfer_report_state_t) States indicating whether a data transfer report is collected yet. [`struct nw_endpoint_type_t`](/documentation/Network/nw_endpoint_type_t) The type of a network endpoint, such as a host or a service. [`struct nw_error_domain_t`](/documentation/Network/nw_error_domain_t) The error domain for errors used by the Network framework. [`struct nw_ethernet_channel_state_t`](/documentation/Network/nw_ethernet_channel_state_t) States indicating whether an Ethernet channel is able to send and receive frames. [`struct nw_framer_start_result_t`](/documentation/Network/nw_framer_start_result_t) Results that you send to indicate the disposition of your protocol after the start handler is invoked. [`struct nw_interface_type_t`](/documentation/Network/nw_interface_type_t) Types of network interfaces, based on their link layer media types. [`struct nw_ip_ecn_flag_t`](/documentation/Network/nw_ip_ecn_flag_t) Flag values for Explicit Congestion Notifications in IP packets. [`struct nw_ip_local_address_preference_t`](/documentation/Network/nw_ip_local_address_preference_t) Types of local addresses that can be selected, such as temporary or stable. [`struct nw_ip_version_t`](/documentation/Network/nw_ip_version_t) IP versions to require on connections and listeners. [`struct nw_listener_state_t`](/documentation/Network/nw_listener_state_t) States indicating whether a listener is able to accept incoming connections. [`struct nw_multipath_service_t`](/documentation/Network/nw_multipath_service_t) Modes in which a connection can support multipath protocols. [`struct nw_parameters_expired_dns_behavior_t`](/documentation/Network/nw_parameters_expired_dns_behavior_t) Options for configuring how expired DNS answers should be used. [`struct nw_path_status_t`](/documentation/Network/nw_path_status_t) Status values indicating whether a path can be used by connections. [`struct nw_report_resolution_protocol_t`](/documentation/Network/nw_report_resolution_protocol_t) A set of transport protocols connections use for DNS resolution. [`struct nw_report_resolution_source_t`](/documentation/Network/nw_report_resolution_source_t) Sources that may provide DNS responses. [`struct nw_service_class_t`](/documentation/Network/nw_service_class_t) Levels of service quality that can be used with a connection. [`struct nw_txt_record_find_key_t`](/documentation/Network/nw_txt_record_find_key_t) Status values describing what kind of value is stored in a TXT record dictionary. [`struct nw_ws_close_code_t`](/documentation/Network/nw_ws_close_code_t) Types of codes used upon closing a WebSocket connection. [`struct nw_ws_opcode_t`](/documentation/Network/nw_ws_opcode_t) Types of messages that you send and receive on a WebSocket connection. [`struct nw_ws_response_status_t`](/documentation/Network/nw_ws_response_status_t) Status values that are sent with a WebSocket server response. [`struct nw_ws_version_t`](/documentation/Network/nw_ws_version_t) Supported versions of the WebSocket protocol. ### C Network Protocols [`protocol OS_nw_advertise_descriptor`](/documentation/Network/OS_nw_advertise_descriptor) [`protocol OS_nw_browse_descriptor`](/documentation/Network/OS_nw_browse_descriptor) [`protocol OS_nw_browse_result`](/documentation/Network/OS_nw_browse_result) [`protocol OS_nw_browser`](/documentation/Network/OS_nw_browser) [`protocol OS_nw_connection`](/documentation/Network/OS_nw_connection) [`protocol OS_nw_connection_group`](/documentation/Network/OS_nw_connection_group) [`protocol OS_nw_content_context`](/documentation/Network/OS_nw_content_context) [`protocol OS_nw_data_transfer_report`](/documentation/Network/OS_nw_data_transfer_report) [`protocol OS_nw_endpoint`](/documentation/Network/OS_nw_endpoint) [`protocol OS_nw_error`](/documentation/Network/OS_nw_error) [`protocol OS_nw_establishment_report`](/documentation/Network/OS_nw_establishment_report) [`protocol OS_nw_ethernet_channel`](/documentation/Network/OS_nw_ethernet_channel) [`protocol OS_nw_framer`](/documentation/Network/OS_nw_framer) [`protocol OS_nw_group_descriptor`](/documentation/Network/OS_nw_group_descriptor) [`protocol OS_nw_interface`](/documentation/Network/OS_nw_interface) [`protocol OS_nw_listener`](/documentation/Network/OS_nw_listener) [`protocol OS_nw_object`](/documentation/Network/OS_nw_object) [`protocol OS_nw_parameters`](/documentation/Network/OS_nw_parameters) [`protocol OS_nw_path`](/documentation/Network/OS_nw_path) [`protocol OS_nw_path_monitor`](/documentation/Network/OS_nw_path_monitor) [`protocol OS_nw_privacy_context`](/documentation/Network/OS_nw_privacy_context) [`protocol OS_nw_protocol_definition`](/documentation/Network/OS_nw_protocol_definition) [`protocol OS_nw_protocol_metadata`](/documentation/Network/OS_nw_protocol_metadata) [`protocol OS_nw_protocol_options`](/documentation/Network/OS_nw_protocol_options) [`protocol OS_nw_protocol_stack`](/documentation/Network/OS_nw_protocol_stack) [`protocol OS_nw_proxy_config`](/documentation/Network/OS_nw_proxy_config) [`protocol OS_nw_relay_hop`](/documentation/Network/OS_nw_relay_hop) [`protocol OS_nw_resolution_report`](/documentation/Network/OS_nw_resolution_report) [`protocol OS_nw_resolver_config`](/documentation/Network/OS_nw_resolver_config) [`protocol OS_nw_txt_record`](/documentation/Network/OS_nw_txt_record) [`protocol OS_nw_ws_request`](/documentation/Network/OS_nw_ws_request) [`protocol OS_nw_ws_response`](/documentation/Network/OS_nw_ws_response) --- Copyright © 2026 Apple Inc. 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