#include <sys/types.h>
#include <sys/socket.h>

#include <netdb.h>
*/
import "C"

import "unsafe"

func cgoNameinfoPTR(b []byte, sa *C.struct_sockaddr, salen C.socklen_t) (int, error) {
	gerrno, err := C.getnameinfo(sa, salen, (*C.char)(unsafe.Pointer(&b[0])), C.size_t(len(b)), nil, 0, C.NI_NAMEREQD)
	return int(gerrno), err

#include <netdb.h>
*/
import "C"

import "unsafe"

const cgoAddrInfoFlags = C.AI_CANONNAME

func cgoNameinfoPTR(b []byte, sa *C.struct_sockaddr, salen C.socklen_t) (int, error) {
	gerrno, err := C.getnameinfo(sa, C.size_t(salen), (*C.char)(unsafe.Pointer(&b[0])), C.size_t(len(b)), nil, 0, C.NI_NAMEREQD)
	return int(gerrno), err

#include <sys/types.h>
#include <sys/socket.h>

#include <netdb.h>
*/
import "C"

import "unsafe"

func cgoNameinfoPTR(b []byte, sa *C.struct_sockaddr, salen C.socklen_t) (int, error) {
	gerrno, err := C.getnameinfo(sa, salen, (*C.char)(unsafe.Pointer(&b[0])), C.socklen_t(len(b)), nil, 0, C.NI_NAMEREQD)
	return int(gerrno), err

	syscall_syscall6(abi.FuncPCABI0(libc_freeaddrinfo_trampoline),
		uintptr(unsafe.Pointer(ai)),
		0, 0, 0, 0, 0)
}

//go:cgo_import_dynamic libc_getnameinfo getnameinfo "/usr/lib/libSystem.B.dylib"
func libc_getnameinfo_trampoline()

func Getnameinfo(sa *syscall.RawSockaddr, salen int, host *byte, hostlen int, serv *byte, servlen int, flags int) (int, error) {

	return x
}

func _C_res_nclose(state *_C_struct___res_state) {
	unix.ResNclose(state)
}

func cgoNameinfoPTR(b []byte, sa *syscall.RawSockaddr, salen int) (int, error) {
	gerrno, err := unix.Getnameinfo(sa, salen, &b[0], len(b), nil, 0, unix.NI_NAMEREQD)
	return int(gerrno), err
}

func cgoSockaddrInet4(ip IP) *syscall.RawSockaddr {
	sa := syscall.RawSockaddrInet4{Len: syscall.SizeofSockaddrInet4, Family: syscall.AF_INET}

	"golang.org/x/net/dns/dnsmessage"
)

// cgoAvailable set to true to indicate that the cgo resolver
// is available on this system.
const cgoAvailable = true

// An addrinfoErrno represents a getaddrinfo, getnameinfo-specific
// error number. It's a signed number and a zero value is a non-error
// by convention.
type addrinfoErrno int

func (eai addrinfoErrno) Error() string   { return _C_gai_strerror(_C_int(eai)) }

It can use a pure Go resolver that sends DNS requests directly to the servers
listed in /etc/resolv.conf, or it can use a cgo-based resolver that calls C
library routines such as getaddrinfo and getnameinfo.

On Unix the pure Go resolver is preferred over the cgo resolver, because a blocked DNS
request consumes only a goroutine, while a blocked C call consumes an operating system thread.