.\"
.\" Copyright 2023 by the c-ares project and its contributors
.\" SPDX-License-Identifier: MIT
.\"
.TH ARES_REINIT 3 "12 November 2023"
.SH NAME
ares_reinit \- ReInitialize a resolver channel from system configuration.
.SH SYNOPSIS
.nf
#include <ares.h>

int ares_reinit(ares_channel_t *\fIchannel\fP)
.fi
.SH DESCRIPTION
The \fBares_reinit(3)\fP function re-reads the system configuration and safely
applies the configuration to the existing channel.  System configuration will
never override user-provided settings such as provided via
\fBares_init_options(3)\fP or \fBares_set_servers(3)\fP.

Any existing queries will be automatically requeued if the server they are
currently assigned to is removed from the system configuration.

This function may cause additional file descriptors to be created, and existing
ones to be destroyed if server configuration has changed.

\Bares_reinit(3)\fP, when compiled with thread safety, will spawn a background
thread to read the configuration and apply it.  It is crucial that developers
use the \fBARES_OPT_SOCK_STATE_CB\fP or \fBARES_OPT_EVENT_THREAD\fP so that
notifications of changes are alerted.  If using \fBares_getsock(3)\fP or
\fBares_fds(3)\fP, no notification is possible which could cause a stall.

.SH RETURN VALUES
\fIares_reinit(3)\fP can return any of the following values:
.TP 14
.B ARES_SUCCESS
Initialization succeeded.
.TP 14
.B ARES_EFILE
A configuration file could not be read.
.TP 14
.B ARES_ENOMEM
The process's available memory was exhausted.

.SH AVAILABILITY
This function was first introduced in c-ares version 1.22.0.
.SH SEE ALSO
.BR ares_init (3),
.BR ares_init_options (3),
.BR ares_destroy (3),
.BR ares_dup (3),
.BR ares_library_init (3),
.BR ares_set_servers (3),
.BR ares_threadsafety (3)