invoke(cmd, args[used-1:])
	base.Exit()
}

// lookupCmd interprets the initial elements of args
// to find a command to run (cmd.Runnable() == true)
// or else a command group that ran out of arguments
// or had an unknown subcommand (len(cmd.Commands) > 0).
// It returns that command and the number of elements of args
// that it took to arrive at that command.
func lookupCmd(args []string) (cmd *base.Command, used int) {
	cmd = base.Go

	if u, err := Current(); err == nil && u.Username == username {
		return u, err
	}
	return lookupUser(username)
}

// LookupId looks up a user by userid. If the user cannot be found, the
// returned error is of type [UnknownUserIdError].
func LookupId(uid string) (*User, error) {
	if u, err := Current(); err == nil && u.Uid == uid {
		return u, err
	}
	return lookupUserId(uid)
}

package user

import "errors"

func lookupUser(string) (*User, error) {
	return nil, errors.New("user: Lookup not implemented on android")
}

func lookupUserId(string) (*User, error) {
	return nil, errors.New("user: LookupId not implemented on android")
}

func lookupGroup(string) (*Group, error) {
	return nil, errors.New("user: LookupGroup not implemented on android")
}

func lookupGroupId(string) (*Group, error) {

	want, err := Current()
	if err != nil {
		if hasCgo || (hasUSER && hasHOME) {
			t.Fatalf("Current: %v", err)
		} else {
			t.Skipf("skipping: %v", err)
		}
	}

	got, err := LookupId(want.Uid)
	if err != nil {
		t.Fatalf("LookupId: %v", err)
	}
	compare(t, want, got)
}

func checkGroup(t *testing.T) {
	t.Helper()
	if !groupImplemented {
		t.Skip("user: group not implemented; skipping test")
	}

// license that can be found in the LICENSE file.

package user

import (
	"fmt"
	"os"
	"syscall"
)

// Partial os/user support on Plan 9.
// Supports Current(), but not Lookup()/LookupId().
// The latter two would require parsing /adm/users.

func init() {
	userImplemented = false
	groupImplemented = false
	groupListImplemented = false
}

var (

				_, err := LookupHost(testNODATA)
				return err
			},
		},
		{
			name: "LookupMX NXDOMAIN",
			query: func() error {
				_, err := LookupMX(testNXDOMAIN)
				return err
			},
		},
		{
			name: "LookupMX NODATA",
			query: func() error {
				_, err := LookupMX(testNODATA)
				return err
			},
		},
		{
			name: "LookupNS NXDOMAIN",

// [Resolver.LookupMX].
func LookupMX(name string) ([]*MX, error) {
	return DefaultResolver.LookupMX(context.Background(), name)
}

// LookupMX returns the DNS MX records for the given domain name sorted by preference.
//
// The returned mail server names are validated to be properly
// formatted presentation-format domain names. If the response contains
// invalid names, those records are filtered out and an error

		return "", e
	}
	return dir, nil
}

// lookupGroupName accepts the name of a group and retrieves the group SID.
func lookupGroupName(groupname string) (string, error) {
	sid, _, t, e := syscall.LookupSID("", groupname)
	if e != nil {
		return "", e
	}
	// https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-samr/7b2aeb27-92fc-41f6-8437-deb65d950921#gt_0387e636-5654-4910-9519-1f8326cf5ec0

	if e != nil {
		return nil, e
	}
	defer LocalFree((Handle)(unsafe.Pointer(sid)))
	return sid.Copy()
}

// LookupSID retrieves a security identifier sid for the account
// and the name of the domain on which the account was found.
// System specify target computer to search.
func LookupSID(system, account string) (sid *SID, domain string, accType uint32, err error) {
	if len(account) == 0 {
		return nil, "", 0, EINVAL
	}

//
// On POSIX systems Gid contains a decimal number representing the group ID.
type Group struct {
	Gid  string // group ID
	Name string // group name
}

// UnknownUserIdError is returned by [LookupId] when a user cannot be found.
type UnknownUserIdError int

func (e UnknownUserIdError) Error() string {
	return "user: unknown userid " + strconv.Itoa(int(e))
}

// UnknownUserError is returned by [Lookup] when