.\"
.\" Copyright 2010 by Ben Greear <greearb@candelatech.com>
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.\" SPDX-License-Identifier: MIT
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.TH ARES_SET_LOCAL_DEV 3 "30 June 2010"
.SH NAME
ares_set_local_dev \- Bind to a specific network device when creating sockets.
.SH SYNOPSIS
.nf
#include <ares.h>

void ares_set_local_dev(ares_channel \fIchannel\fP, const char* \fIlocal_dev_name\fP)
.fi
.SH DESCRIPTION
The \fBares_set_local_dev\fP function causes all future sockets
to be bound to this device with SO_BINDTODEVICE.  This forces communications
to go over a certain interface, which can be useful on multi-homed machines.
This option is only supported on Linux, and root privileges are required
for the option to work.  If SO_BINDTODEVICE is not supported or the
setsocktop call fails (probably because of permissions), the error is
silently ignored.
.SH SEE ALSO
.BR ares_set_local_ip4 (3)
.BR ares_set_local_ip6 (3)
.SH NOTES
This function was added in c-ares 1.7.4
.SH AUTHOR
Ben Greear