:relfileprefix: ../../../ [#boost-urls-ipv6_address-2constructor-08] = xref:boost.adoc[pass:[boost]]::xref:boost/urls.adoc[pass:[urls]]::xref:boost/urls/ipv6_address.adoc[pass:[ipv6_address]]::ipv6_address Construct from an IPv4 address. == Synopsis Declared in header `` [source,cpp,subs="verbatim,macros,-callouts"] ---- ipv6_address(xref:boost/urls/ipv4_address.adoc[ipv4_address] const& addr) noexcept; ---- == Description This function constructs an IPv6 address from the IPv4 address `addr`. The resulting address is an IPv4-Mapped IPv6 Address. === Specification * link:https://datatracker.ietf.org/doc/html/rfc4291#section-2.5.5.2[2.5.5.2. IPv4-Mapped IPv6 Address (rfc4291)] == Parameters |=== | Name | Description | *addr* | The address to construct from. |===