.\" Copyright, the authors of the Linux man-pages project .\" .\" SPDX-License-Identifier: Linux-man-pages-copyleft .\" .TH IPV6_MTU_DISCOVER 2const 2025-12-02 "Linux man-pages 6.17" .SH NAME IPV6_MTU_DISCOVER \- path maximum transfer unit size discovery .SH LIBRARY Standard C library .RI ( libc ,\~ \-lc ) .SH SYNOPSIS .nf .BR "#include " " /* Definition of " IP* " constants */" .B #include .P .BI int\~setsockopt(int\~ sockfd ,\~IPPROTO_IPV6,\~IPV6_MTU_DISCOVER, .BI " const\~int\~*" val ,\~sizeof(int)); .BI int\~getsockopt(int\~ sockfd ,\~IPPROTO_IPV6,\~IPV6_MTU_DISCOVER, .BI " int\~*" val ,\~sizeof(int)); .fi .SH DESCRIPTION Set or receive the Path MTU Discovery setting for a socket. .P See .BR IP_MTU_DISCOVER (2const). .SH ERRORS See .BR IPPROTO_IPV6 (2const). See .BR setsockopt (2). See .BR ipv6 (7). .SH SEE ALSO .BR IPPROTO_IPV6 (2const), .BR setsockopt (2), .BR ipv6 (7)