= libnng(3)
//
// Copyright 2024 Staysail Systems, Inc. <info@staysail.tech>
// Copyright 2018 Capitar IT Group BV <info@capitar.com>
// Copyright 2019 Devolutions <info@devolutions.net>
// Copyright 2020 Dirac Research <robert.bielik@dirac.com>
//
// This document is supplied under the terms of the MIT License, a
// copy of which should be located in the distribution where this
// file was obtained (LICENSE.txt).  A copy of the license may also be
// found online at https://opensource.org/licenses/MIT.
//

== NAME

libnng - nanomsg next generation library

== SYNOPSIS

*cc* [_flags_] _files_ *-lnng* [_libraries_]

== DESCRIPTION

xref:nng.7.adoc[_NNG_] provides a common messaging framework
intended to solve common communication problems in distributed applications.

It provides a C language API.

=== Common Functions

The following common functions exist in _libnng_.

|===
|xref:nng_alloc.3.adoc[nng_alloc]|allocate memory
|xref:nng_free.3.adoc[nng_free]|free memory
|xref:nng_strdup.3.adoc[nng_strdup]|duplicate string
|xref:nng_strerror.3.adoc[nng_strerror]|return an error description
|xref:nng_strfree.3.adoc[nng_strfree]|free string
|xref:nng_version.3.adoc[nng_version]|report library version
|===

=== Socket Functions

The following functions operate on sockets.

|===
|xref:nng_close.3.adoc[nng_close]|close socket
|xref:nng_dial.3.adoc[nng_dial]|create and start dialer
|xref:nng_getopt.3.adoc[nng_getopt]|get socket option
|xref:nng_listen.3.adoc[nng_listen]|create and start listener
|xref:nng_recv.3.adoc[nng_recv]|receive data
|xref:nng_send.3.adoc[nng_send]|send data
|xref:nng_setopt.3.adoc[nng_setopt]|set socket option (DEPRECATED)
|xref:nng_socket_get.3.adoc[nng_socket_get]|get socket option
|xref:nng_socket_id.3.adoc[nng_socket_id]|get numeric socket identifier
|xref:nng_socket_raw.3.adoc[nng_socket_raw]|is the socket raw
|xref:nng_socket_proto_id.3.adoc[nng_socket_proto_id]|get the socket protocol identifier
|xref:nng_socket_proto_name.3.adoc[nng_socket_proto_name]|get the socket protocol name
|xref:nng_socket_set.3.adoc[nng_socket_set]|set socket option
|xref:nng_sub_susbcribe.3.adoc[nng_sub_subscribe]|manage subscriptions
|===

=== Connection Management

The following functions are used with either listeners, or dialers.
Listeners accept incoming connection requests, and dialers make them.

|===
|xref:nng_dial.3.adoc[nng_dial]|create and start dialer
|xref:nng_dialer_close.3.adoc[nng_dialer_close]|close dialer
|xref:nng_dialer_create.3.adoc[nng_dialer_create]|create dialer
|xref:nng_dialer_get.3.adoc[nng_dialer_get]|get dialer option
|xref:nng_dialer_getopt.3.adoc[nng_dialer_getopt]|get dialer option (DEPRECATED)
|xref:nng_dialer_id.3.adoc[nng_dialer_id]|get numeric dialer identifier
|xref:nng_dialer_set.3.adoc[nng_dialer_set]|set dialer option
|xref:nng_dialer_setopt.3.adoc[nng_dialer_setopt]|set dialer option (DEPRECATED)
|xref:nng_dialer_start.3.adoc[nng_dialer_start]|start dialer
|xref:nng_listen.3.adoc[nng_listen]|create and start listener
|xref:nng_listener_close.3.adoc[nng_listener_close]|close listener
|xref:nng_listener_create.3.adoc[nng_listener_create]|create listener
|xref:nng_listener_get.3.adoc[nng_listener_get]|get listener option
|xref:nng_listener_getopt.3.adoc[nng_listener_getopt]|get listener option (DEPRECATED)
|xref:nng_listener_id.3.adoc[nng_listener_id]|get numeric listener identifier
|xref:nng_listener_set.3.adoc[nng_listener_set]|set listener option
|xref:nng_listener_setopt.3.adoc[nng_listener_setopt]|set listener option (DEPRECATED)
|xref:nng_listener_start.3.adoc[nng_listener_start]|start listener
|xref:nng_pipe_close.3.adoc[nng_pipe_close]|close pipe
|xref:nng_pipe_dialer.3.adoc[nng_pipe_dialer]|return dialer that created pipe
|xref:nng_pipe_get.3.adoc[nng_pipe_get]|get pipe option
|xref:nng_pipe_getopt.3.adoc[nng_pipe_getopt]|get pipe option (DEPRECATED)
|xref:nng_pipe_id.3.adoc[nng_pipe_id]|get numeric pipe identifier
|xref:nng_pipe_listener.3.adoc[nng_pipe_listener]|return listener that created pipe
|xref:nng_pipe_notify.3.adoc[nng_pipe_notify]|register pipe notification callback
|xref:nng_pipe_socket.3.adoc[nng_pipe_socket]|return owning socket for pipe
|===

=== Message Handling Functions

Applications desiring to use the richest part of _libnng_ will want to
use the message API, where a message structure is passed between functions.
This API provides the most power support for zero-copy.

Messages are divided into a header and body, where the body generally carries
user-payload and the header carries protocol specific header information.
Most applications will only interact with the body.

|===
|xref:nng_msg_alloc.3.adoc[nng_msg_alloc]|allocate a message
|xref:nng_msg_append.3.adoc[nng_msg_append]|append to message body
|xref:nng_msg_body.3.adoc[nng_msg_body]|return message body
|xref:nng_msg_capacity.3.adoc[nng_msg_capacity]|return capacity allocated for message body
|xref:nng_msg_chop.3.adoc[nng_msg_chop]|remove data from end of message body
|xref:nng_msg_clear.3.adoc[nng_msg_clear]|clear message body
|xref:nng_msg_dup.3.adoc[nng_msg_dup]|duplicate a message
|xref:nng_msg_free.3.adoc[nng_msg_free]|free a message
|xref:nng_msg_get_pipe.3.adoc[nng_msg_get_pipe]|get pipe for message
|xref:nng_msg_insert.3.adoc[nng_msg_insert]|prepend to message body
|xref:nng_msg_len.3.adoc[nng_msg_len]|return the message body length
|xref:nng_msg_realloc.3.adoc[nng_msg_realloc]|reallocate a message
|xref:nng_msg_reserve.3.adoc[nng_msg_reserve]|reserve storage for message body
|xref:nng_msg_set_pipe.3.adoc[nng_msg_set_pipe]|set pipe for message
|xref:nng_msg_trim.3.adoc[nng_msg_trim]|remove data from start of message body
|xref:nng_recvmsg.3.adoc[nng_recvmsg]|receive a message
|xref:nng_sendmsg.3.adoc[nng_sendmsg]|send a message
|===

==== Message Header Handling

TIP: Few applications will need these functions, as message headers are only
used to carry protocol-specific content.  However, applications which use raw
mode may need to access the header of messages.

|===
|xref:nng_msg_header.3.adoc[nng_msg_header]|return message header
|xref:nng_msg_header_append.3.adoc[nng_msg_header_append]|append to message header
|xref:nng_msg_header_chop.3.adoc[nng_msg_header_chop]|remove data from end of message header
|xref:nng_msg_header_clear.3.adoc[nng_msg_header_clear]|clear message header
|xref:nng_msg_header_insert.3.adoc[nng_msg_header_insert]|prepend to message header
|xref:nng_msg_header_len.3.adoc[nng_msg_header_len]|return the message header length
|xref:nng_msg_header_trim.3.adoc[nng_msg_header_trim]|remove data from start of message header
|===

=== Asynchronous Operations

Most applications will interact with _NNG_ synchronously; that is that
functions such as xref:nng_send.3.adoc[`nng_send`] will block the calling
thread until the operation has completed.

NOTE: Synchronous operations which send messages may return before the
message has actually been received, or even transmitted.  Instead, These
functions return as soon as the message was successfully queued for
delivery.

Asynchronous operations behave differently.  These operations are
initiated by the calling thread, but control returns immediately to
the calling thread.  When the operation is subsequently completed (regardless
of whether this was successful or not), then a user supplied function
is executed.

A context structure, an xref:nng_aio.5.adoc[`nng_aio`], is allocated and
associated with each asynchronous operation.
Only a single asynchronous operation may be associated with an
`nng_aio` at any time.

The following functions are used in the asynchronous model:

|===
|xref:nng_aio_abort.3.adoc[nng_aio_abort]|abort asynchronous I/O operation
|xref:nng_aio_alloc.3.adoc[nng_aio_alloc]|allocate asynchronous I/O handle
|xref:nng_aio_begin.3.adoc[nng_aio_begin]|begin asynchronous I/O operation
|xref:nng_aio_busy.3.adoc[nng_aio_busy]|test if asynchronous I/O is busy
|xref:nng_aio_cancel.3.adoc[nng_aio_cancel]|cancel asynchronous I/O operation
|xref:nng_aio_count.3.adoc[nng_aio_count]|return number of bytes transferred
|xref:nng_aio_defer.3.adoc[nng_aio_defer]|defer asynchronous I/O operation
|xref:nng_aio_finish.3.adoc[nng_aio_finish]|finish asynchronous I/O operation
|xref:nng_aio_free.3.adoc[nng_aio_free]|free asynchronous I/O handle
|xref:nng_aio_get_input.3.adoc[nng_aio_get_input]|return input parameter
|xref:nng_aio_get_msg.3.adoc[nng_aio_get_msg]|get message from an asynchronous receive
|xref:nng_aio_get_output.3.adoc[nng_aio_get_output]|return output result
|xref:nng_aio_free.3.adoc[nng_aio_reap]|reap asynchronous I/O handle
|xref:nng_aio_result.3.adoc[nng_aio_result]|return result of asynchronous operation
|xref:nng_aio_set_input.3.adoc[nng_aio_set_input]|set input parameter
|xref:nng_aio_set_iov.3.adoc[nng_aio_set_iov]|set scatter/gather vector
|xref:nng_aio_set_msg.3.adoc[nng_aio_set_msg]|set message for an asynchronous send
|xref:nng_aio_set_output.3.adoc[nng_aio_set_output]|set output result
|xref:nng_aio_set_timeout.3.adoc[nng_aio_set_timeout]|set asynchronous I/O timeout
|xref:nng_aio_stop.3.adoc[nng_aio_stop]|stop asynchronous I/O operation
|xref:nng_aio_wait.3.adoc[nng_aio_wait]|wait for asynchronous I/O operation
|xref:nng_recv_aio.3.adoc[nng_recv_aio]|receive message asynchronously
|xref:nng_send_aio.3.adoc[nng_send_aio]|send message asynchronously
|xref:nng_sleep_aio.3.adoc[nng_sleep_aio]|sleep asynchronously
|===

=== Protocols

The following functions are used to construct a socket with a specific protocol:

|===
|xref:nng_bus_open.3.adoc[nng_bus_open]|open a bus socket
|xref:nng_pair_open.3.adoc[nng_pair_open]|open a pair socket
|xref:nng_pub_open.3.adoc[nng_pub_open]|open a pub socket
|xref:nng_pull_open.3.adoc[nng_pull_open]|open a pull socket
|xref:nng_push_open.3.adoc[nng_push_open]|open a push socket
|xref:nng_rep_open.3.adoc[nng_rep_open]|open a rep socket
|xref:nng_req_open.3.adoc[nng_req_open]|open a req socket
|xref:nng_respondent_open.3.adoc[nng_respondent_open]|open a respondent socket
|xref:nng_sub_open.3.adoc[nng_sub_open]|open a sub socket
|xref:nng_surveyor_open.3.adoc[nng_surveyor_open]|open a surveyor socket
|===

=== Transports

The following functions are used to register a transport for use.
This is no longer necessary, and applications should not call these
functions anymore.

|===
| xref:nng_inproc_register.3.adoc[nng_inproc_register]|register inproc transport (DEPRECATED)
| xref:nng_ipc_register.3.adoc[nng_ipc_register]|register IPC transport (DEPRECATED)
| xref:nng_tcp_register.3.adoc[nng_tcp_register]|register TCP transport (DEPRECATED)
| xref:nng_tls_register.3.adoc[nng_tls_register]|register TLS transport (DEPRECATED)
| xref:nng_ws_register.3.adoc[nng_ws_register]|register WebSocket transport (DEPRECATED)
| xref:nng_wss_register.3.adoc[nng_wss_register]|register WebSocket Secure transport (DEPRECATED)
| xref:nng_zt_register.3.adoc[nng_zt_register]|register ZeroTier transport (DEPRECATED)
|===

=== Protocol Contexts

The following functions are useful to separate the protocol processing
from a socket object, into a separate context.
This can allow multiple contexts to be created on a single socket for
concurrent applications.

|===
|xref:nng_ctx_close.3.adoc[nng_ctx_close]|close context
|xref:nng_ctx_get.3.adoc[nng_ctx_get]|get context option
|xref:nng_ctx_getopt.3.adoc[nng_ctx_getopt]|get context option (DEPRECATED)
|xref:nng_ctx_id.3.adoc[nng_ctx_id]|get numeric context identifier
|xref:nng_ctx_open.3.adoc[nng_ctx_open]|create context
|xref:nng_ctx_recv.3.adoc[nng_ctx_recv]|receive message using context asynchronously
|xref:nng_ctx_recvmsg.3.adoc[nng_ctx_recvmsg]|receive a message using context
|xref:nng_ctx_send.3.adoc[nng_ctx_send]|send message using context asynchronously
|xref:nng_ctx_sendmsg.3.adoc[nng_ctx_sendmsg]|send a message using context
|xref:nng_ctx_set.3.adoc[nng_ctx_set]|set context option
|xref:nng_ctx_setopt.3.adoc[nng_ctx_setopt]|set context option (DEPRECATED)
|===

=== Devices, Relays

The following function family is used to create forwarders or relayers
that route messages from one socket to another.

|===
|xref:nng_device.3.adoc[nng_device]|message forwarding device
|===

=== Statistics

The following functions provide access to statistics which can be used
to observe program behaviors and as an aid in troubleshooting.

|===
|xref:nng_stat_bool.3.adoc[nng_stat_bool]|get statistic Boolean value
|xref:nng_stat_child.3.adoc[nng_stat_child]|get child statistic
|xref:nng_stat_desc.3.adoc[nng_stat_name]|get statistic description
|xref:nng_stat_find.3.adoc[nng_stat_find]|find statistic by name
|xref:nng_stat_find_dialer.3.adoc[nng_stat_find_dialer]|find dialer statistics
|xref:nng_stat_find_listener.3.adoc[nng_stat_find_listener]|find listener statistics
|xref:nng_stat_find_socket.3.adoc[nng_stat_find_socket]|find socket statistics
|xref:nng_stat_name.3.adoc[nng_stat_name]|get statistic name
|xref:nng_stat_next.3.adoc[nng_stat_next]|get next statistic
|xref:nng_stat_string.3.adoc[nng_stat_string]|get statistic string value
|xref:nng_stat_timestamp.3.adoc[nng_stat_timestamp]|get statistic timestamp
|xref:nng_stat_type.3.adoc[nng_stat_type]|get statistic type
|xref:nng_stat_unit.3.adoc[nng_stat_unit]|get statistic unit
|xref:nng_stat_value.3.adoc[nng_stat_value]|get statistic numeric value
|xref:nng_stats_free.3.adoc[nng_stats_free]|free statistics
|xref:nng_stats_get.3.adoc[nng_stats_get]|get statistics
|===

=== URL Object

Common functionality is supplied for parsing and handling
universal resource locators (URLS).

|===
|xref:nng_url_clone.3.adoc[nng_url_clone]|clone URL structure
|xref:nng_url_free.3.adoc[nng_url_free]|free URL structure
|xref:nng_url_parse.3.adoc[nng_url_parse]|create URL structure from string
|===

=== Logging Support

Common functionality for message logging.

|===
|xref:nng_log.3.adoc[nng_log]|log a message
|xref:nng_log_facility.3.adoc[nng_log_set_facility]|set log facility
|xref:nng_log_level.3.adoc[nng_log_set_level]|set log level
|xref:nng_log_logger.3.adoc[nng_log_set_logger]|set logging handler
|===

=== Supplemental API

These supplemental functions are not intrinsic to building
network applications with _NNG_, but they are made available
as a convenience to aid in creating portable applications.

|===
|xref:nng_clock.3supp.adoc[nng_clock]|get time
|xref:nng_cv_alloc.3supp.adoc[nng_cv_alloc]|allocate condition variable
|xref:nng_cv_free.3supp.adoc[nng_cv_free]|free condition variable
|xref:nng_cv_until.3supp.adoc[nng_cv_until]|wait for condition or timeout
|xref:nng_cv_wait.3supp.adoc[nng_cv_wait]|wait for condition
|xref:nng_cv_wake.3supp.adoc[nng_cv_wake]|wake all waiters
|xref:nng_cv_wake1.3supp.adoc[nng_cv_wake1]|wake one waiter
|xref:nng_id_map.3supp.adoc[nng_id_map]|identifier based mapping table
|xref:nng_msleep.3supp.adoc[nng_msleep]|sleep for milliseconds
|xref:nng_mtx_alloc.3supp.adoc[nng_mtx_alloc]|allocate mutex
|xref:nng_mtx_free.3supp.adoc[nng_mtx_free]|free mutex
|xref:nng_mtx_lock.3supp.adoc[nng_mtx_lock]|lock mutex
|xref:nng_mtx_unlock.3supp.adoc[nng_mtx_unlock]|unlock mutex
|xref:nng_opts_parse.3supp.adoc[nng_opts_parse]|parse command line options
|xref:nng_random.3supp.adoc[nng_random]|get random number
|xref:nng_socket_pair.3supp.adoc[nng_socket_pair]|create connected pair of BSD sockets
|xref:nng_thread_create.3supp.adoc[nng_thread_create]|create thread
|xref:nng_thread_destroy.3supp.adoc[nng_thread_destroy]|reap thread
|xref:nng_thread_set_name.3supp.adoc[nng_thread_set_name]|set thread name
|===

=== Byte Streams

These functions are available for use with byte streams.
They are considered low-level, for uses where the higher level functions
using Scalability Protocols are inappropriate.

Byte streams, represented by
xref:nng_stream.5.adoc[`nng_stream`] objects, correspond to underlying
connections such as TCP connections or named pipes.
They are created by either
xref:nng_stream_dialer.5.adoc[`nng_stream_dialer`] or
xref:nng_stream_listener.5.adoc[`nng_stream_listener`] objects.

|===
|xref:nng_stream_close.3str.adoc[nng_stream_close]|close byte stream
|xref:nng_stream_dialer_alloc.3str.adoc[nng_stream_dialer_alloc]|allocate byte stream dialer
|xref:nng_stream_dialer_close.3str.adoc[nng_stream_dialer_close]|close byte stream dialer
|xref:nng_stream_dialer_dial.3str.adoc[nng_stream_dialer_dial]|initiate outgoing byte stream
|xref:nng_stream_dialer_free.3str.adoc[nng_stream_dialer_free]|free byte stream dialer
|xref:nng_stream_dialer_get.3str.adoc[nng_stream_dialer_get]|get option from byte stream dialer
|xref:nng_stream_dialer_set.3str.adoc[nng_stream_dialer_set]|set option on byte stream dialer
|xref:nng_stream_free.3str.adoc[nng_stream_free]|free byte stream
|xref:nng_stream_get.3str.adoc[nng_stream_get]|get option from byte stream
|xref:nng_stream_listener_accept.3str.adoc[nng_stream_listener_accept]|accept incoming byte stream
|xref:nng_stream_listener_alloc.3str.adoc[nng_stream_listener_alloc]|allocate byte stream listener
|xref:nng_stream_listener_close.3str.adoc[nng_stream_listener_close]|close byte stream listener
|xref:nng_stream_listener_free.3str.adoc[nng_stream_listener_free]|free byte stream listener
|xref:nng_stream_listener_get.3str.adoc[nng_stream_listener_get]|get option from byte stream listener
|xref:nng_stream_listener_listen.3str.adoc[nng_stream_listener_listen]|bind byte stream listener to address
|xref:nng_stream_listener_set.3str.adoc[nng_stream_listener_set]|set option on byte stream listener
|xref:nng_stream_recv.3str.adoc[nng_stream_recv]|receive from byte stream
|xref:nng_stream_send.3str.adoc[nng_stream_send]|send to byte stream
|xref:nng_stream_set.3str.adoc[nng_stream_set]|set option on byte stream
|===

=== HTTP Support

The library may be configured with support for HTTP, and this will
be the case if WebSocket support is configured as well.
In this case, it is possible to access functionality to support the creation of
HTTP (and HTTP/S if TLS support is present) servers and clients.

==== Common HTTP Functions

The following functions are used to work with HTTP requests, responses,
and connections.

|===
|xref:nng_http_conn_close.3http.adoc[nng_http_conn_close]|close HTTP connection
|xref:nng_http_conn_read.3http.adoc[nng_http_conn_read]|read from HTTP connection
|xref:nng_http_conn_read_all.3http.adoc[nng_http_conn_read_all]|read all from HTTP connection
|xref:nng_http_conn_read_req.3http.adoc[nng_http_conn_read_req]|read HTTP request
|xref:nng_http_conn_read_res.3http.adoc[nng_http_conn_read_res]|read HTTP response
|xref:nng_http_conn_write.3http.adoc[nng_http_conn_write]|write to HTTP connection
|xref:nng_http_conn_write_all.3http.adoc[nng_http_conn_write_all]|write all to HTTP connection
|xref:nng_http_conn_write_req.3http.adoc[nng_http_conn_write_req]|write HTTP request
|xref:nng_http_conn_write_res.3http.adoc[nng_http_conn_write_res]|write HTTP response
|xref:nng_http_req_add_header.3http.adoc[nng_http_req_add_header]|add HTTP request header
|xref:nng_http_req_alloc.3http.adoc[nng_http_req_alloc]|allocate HTTP request structure
|xref:nng_http_req_copy_data.3http.adoc[nng_http_req_copy_data]|copy HTTP request body
|xref:nng_http_req_del_header.3http.adoc[nng_http_req_del_header]|delete HTTP request header
|xref:nng_http_req_free.3http.adoc[nng_http_req_free]|free HTTP request structure
|xref:nng_http_req_get_data.3http.adoc[nng_http_req_get_data]|get HTTP request body
|xref:nng_http_req_get_header.3http.adoc[nng_http_req_get_header]|return HTTP request header
|xref:nng_http_req_get_method.3http.adoc[nng_http_req_get_method]|return HTTP request method
|xref:nng_http_req_get_uri.3http.adoc[nng_http_req_get_uri]|return HTTP request URI
|xref:nng_http_req_get_version.3http.adoc[nng_http_req_get_version]|return HTTP request protocol version
|xref:nng_http_req_reset.3http.adoc[nng_http_req_reset]|reset HTTP request structure
|xref:nng_http_req_set_data.3http.adoc[nng_http_req_set_data]|set HTTP request body
|xref:nng_http_req_set_header.3http.adoc[nng_http_req_set_header]|set HTTP request header
|xref:nng_http_req_set_method.3http.adoc[nng_http_req_set_method]|set HTTP request method
|xref:nng_http_req_set_uri.3http.adoc[nng_http_req_set_uri]|set HTTP request URI
|xref:nng_http_req_set_version.3http.adoc[nng_http_req_set_version]|set HTTP request protocol version
|xref:nng_http_res_add_header.3http.adoc[nng_http_res_add_header]|add HTTP response header
|xref:nng_http_res_alloc.3http.adoc[nng_http_res_alloc]|allocate HTTP response structure
|xref:nng_http_res_alloc_error.3http.adoc[nng_http_res_alloc_error]|allocate HTTP error response
|xref:nng_http_res_copy_data.3http.adoc[nng_http_res_copy_data]|copy HTTP response body
|xref:nng_http_res_del_header.3http.adoc[nng_http_res_del_header]|delete HTTP response header
|xref:nng_http_res_free.3http.adoc[nng_http_res_free]|free HTTP response structure
|xref:nng_http_res_get_data.3http.adoc[nng_http_res_get_data]|get HTTP response body
|xref:nng_http_res_get_header.3http.adoc[nng_http_res_get_header]|return HTTP response header
|xref:nng_http_res_get_reason.3http.adoc[nng_http_res_get_reason]|return HTTP response reason
|xref:nng_http_res_get_status.3http.adoc[nng_http_res_get_status]|return HTTP response status
|xref:nng_http_res_get_version.3http.adoc[nng_http_res_get_version]|return HTTP response protocol version
|xref:nng_http_res_reset.3http.adoc[nng_http_res_reset]|reset HTTP response structure
|xref:nng_http_res_set_data.3http.adoc[nng_http_res_set_data]|set HTTP response body
|xref:nng_http_res_set_header.3http.adoc[nng_http_res_set_header]|set HTTP response header
|xref:nng_http_res_set_reason.3http.adoc[nng_http_res_set_reason]|set HTTP response reason
|xref:nng_http_res_set_status.3http.adoc[nng_http_res_set_status]|set HTTP response status
|xref:nng_http_res_set_version.3http.adoc[nng_http_res_set_version]|set HTTP response protocol version
|===

==== HTTP Client Functions

These functions are intended for use with HTTP client applications.

|===
|xref:nng_http_client_alloc.3http.adoc[nng_http_client_alloc]|allocate HTTP client
|xref:nng_http_client_connect.3http.adoc[nng_http_client_connect]|establish HTTP client connection
|xref:nng_http_client_free.3http.adoc[nng_http_client_free]|free HTTP client
|xref:nng_http_client_get_tls.3http.adoc[nng_http_client_get_tls]|get HTTP client TLS configuration
|xref:nng_http_client_set_tls.3http.adoc[nng_http_client_set_tls]|set HTTP client TLS configuration
|xref:nng_http_client_transact.3http.adoc[nng_http_client_transact]|perform one HTTP transaction
|xref:nng_http_conn_transact.3http.adoc[nng_http_conn_transact]|perform one HTTP transaction on connection
|===

==== HTTP Server Functions

These functions are intended for use with HTTP server applications.

|===
|xref:nng_http_handler_alloc.3http.adoc[nng_http_handler_alloc]|allocate HTTP server handler
|xref:nng_http_handler_collect_body.3http.adoc[nng_http_handler_collect_body]|set HTTP handler to collect request body
|xref:nng_http_handler_free.3http.adoc[nng_http_handler_free]|free HTTP server handler
|xref:nng_http_handler_get_data.3http.adoc[nng_http_handler_get_data]|return extra data for HTTP handler
|xref:nng_http_handler_set_data.3http.adoc[nng_http_handler_set_data]|set extra data for HTTP handler
|xref:nng_http_handler_set_host.3http.adoc[nng_http_handler_set_host]|set host for HTTP handler
|xref:nng_http_handler_set_method.3http.adoc[nng_http_handler_set_method]|set HTTP handler method
|xref:nng_http_handler_set_tree.3http.adoc[nng_http_handler_set_tree]|set HTTP handler to match trees
|xref:nng_http_hijack.3http.adoc[nng_http_hijack]|hijack HTTP server connection
|xref:nng_http_server_add_handler.3http.adoc[nng_http_server_add_handler]|add HTTP server handler
|xref:nng_http_server_del_handler.3http.adoc[nng_http_server_del_handler]|delete HTTP server handler
|xref:nng_http_server_get_addr.3http.adoc[nng_http_server_get_addr]|get HTTP server address
|xref:nng_http_server_get_tls.3http.adoc[nng_http_server_get_tls]|get HTTP server TLS configuration
|xref:nng_http_server_hold.3http.adoc[nng_http_server_hold]|get and hold HTTP server instance
|xref:nng_http_server_release.3http.adoc[nng_http_server_release]|release HTTP server instance
|xref:nng_http_server_set_error_file.3http.adoc[nng_http_server_set_error_file]|set custom HTTP error file
|xref:nng_http_server_set_error_page.3http.adoc[nng_http_server_set_error_page]|set custom HTTP error page
|xref:nng_http_server_set_tls.3http.adoc[nng_http_server_set_tls]|set HTTP server TLS configuration
|xref:nng_http_server_res_error.3http.adoc[nng_http_server_res_error]|use HTTP server error page
|xref:nng_http_server_start.3http.adoc[nng_http_server_start]|start HTTP server
|xref:nng_http_server_stop.3http.adoc[nng_http_server_stop]|stop HTTP server
|===

=== TLS Configuration Objects

The following functions are used to manipulate transport layer security
(TLS) configuration objects.  Most of these functions will not be used even
by TLS applications.

NOTE: These functions will only be present if the library has been built
with TLS support.

|===
|xref:nng_tls_config_alloc.3tls.adoc[nng_tls_config_alloc]|allocate TLS configuration
|xref:nng_tls_config_auth_mode.3tls.adoc[nng_tls_config_auth_mode]|set authentication mode
|xref:nng_tls_config_ca_chain.3tls.adoc[nng_tls_config_ca_chain]|set certificate authority chain
|xref:nng_tls_config_ca_file.3tls.adoc[nng_tls_config_ca_file]|load certificate authority from file
|xref:nng_tls_config_cert_key_file.3tls.adoc[nng_tls_config_cert_key_file]|load own certificate and key from file
|xref:nng_tls_config_psk.3tls.adoc[nng_tls_config_psk]|set pre-shared key and identity
|xref:nng_tls_config_own_cert.3tls.adoc[nng_tls_config_own_cert]|set own certificate and key
|xref:nng_tls_config_free.3tls.adoc[nng_tls_config_free]|free TLS configuration
|xref:nng_tls_config_server_name.3tls.adoc[nng_tls_config_server_name]|set remote server name
|===


== SEE ALSO

[.text-left]
xref:nng_compat.3compat.adoc[nng_compat(3compat)],
xref:nng.7.adoc[nng(7)]
