fallthrough
	case syscall.O_WRONLY | syscall.O_CREAT:
		access = syscall.GENERIC_READ | syscall.GENERIC_WRITE
	case syscall.O_WRONLY | syscall.O_CREAT | syscall.O_APPEND:
		access = syscall.FILE_APPEND_DATA
	default:
		return nil, fmt.Errorf("Unsupported flag (%d)", flag)
	}

	var createflag uint32
	switch {
	case flag&syscall.O_CREAT == syscall.O_CREAT:
		createflag = syscall.OPEN_ALWAYS
	default:

		fallthrough
	case syscall.O_RDWR | syscall.O_CREAT:
		lockType |= syscall.LOCK_EX
	default:
		return nil, &os.PathError{
			Op:   "open",
			Path: path,
			Err:  syscall.EINVAL,
		}
	}

	f, err := os.OpenFile(path, flag|syscall.O_SYNC, perm)
	if err != nil {
		return nil, err
	}

	if err = syscall.Flock(int(f.Fd()), lockType); err != nil {
		f.Close()
		if err == syscall.EWOULDBLOCK {
			err = ErrAlreadyLocked

package cmd

import (
	"errors"
	"os"
	"runtime"
	"syscall"
)

// No space left on device error
func isSysErrNoSpace(err error) bool {
	return errors.Is(err, syscall.ENOSPC)
}

// Invalid argument, unsupported flags such as O_DIRECT
func isSysErrInvalidArg(err error) bool {
	return errors.Is(err, syscall.EINVAL)
}

// Input/output error
func isSysErrIO(err error) bool {

package lock

import (
	"os"
	"syscall"
)

// lockedOpenFile is an internal function.
func lockedOpenFile(path string, flag int, perm os.FileMode, rlockType int) (*LockedFile, error) {
	var lockType int16
	switch flag {
	case syscall.O_RDONLY:
		lockType = syscall.F_RDLCK
	case syscall.O_WRONLY:
		fallthrough
	case syscall.O_RDWR:
		fallthrough
	case syscall.O_WRONLY | syscall.O_CREAT:
		fallthrough

package cmd

import (
	"os"
	"runtime"
	"syscall"
	"testing"
)

func TestSysErrors(t *testing.T) {
	pathErr := &os.PathError{Err: syscall.ENAMETOOLONG}
	ok := isSysErrTooLong(pathErr)
	if !ok {
		t.Fatalf("Unexpected error expecting %s", syscall.ENAMETOOLONG)
	}
	pathErr = &os.PathError{Err: syscall.ENOTDIR}
	ok = isSysErrNotDir(pathErr)
	if !ok {

	globAllP, err := syscall.UTF16PtrFromString(globAll)
	if err != nil {
		return nil, errInvalidArgument
	}
	data := &syscall.Win32finddata{}
	handle, err := syscall.FindFirstFile(globAllP, data)
	if err != nil {
		return nil, syscallErrToFileErr(dirPath, err)
	}

	defer syscall.FindClose(handle)

	count := opts.count
	for ; count != 0; err = syscall.FindNextFile(handle, data) {

				err = pe.Err
			}
			if se, ok := err.(syscall.Errno); ok && (se == syscall.EAGAIN || se == syscall.EMFILE) {
				time.Sleep(time.Millisecond)
				continue
			}

			t.Error(err)
			return
		}
		cmds = append(cmds, cmd)
	}

	failures := 0
	for _, cmd := range cmds {
		err := cmd.Wait()
		if err == nil {
			continue
		}

		t.Errorf("syscall.Exec failed: %v\n%s", err, cmd.Stdout)

package disk

import (
	"syscall"
)

// SameDisk reports whether di1 and di2 describe the same disk.
func SameDisk(disk1, disk2 string) (bool, error) {
	st1 := syscall.Stat_t{}
	st2 := syscall.Stat_t{}

	if err := syscall.Stat(disk1, &st1); err != nil {
		return false, err
	}

	if err := syscall.Stat(disk2, &st2); err != nil {
		return false, err
	}

		entries, err := readDirN(dirname, 1)
		if err != nil {
			return false
		}
		return len(entries) == 0
	}
	var stat syscall.Stat_t
	if err := syscall.Stat(dirname, &stat); err != nil {
		return false
	}
	return stat.Mode&syscall.S_IFMT == syscall.S_IFDIR && stat.Nlink == 2

pkg net, type ListenConfig struct, KeepAliveConfig KeepAliveConfig #62254
pkg syscall (windows-386), const WSAENOPROTOOPT = 10042 #62254
pkg syscall (windows-386), const WSAENOPROTOOPT Errno #62254
pkg syscall (windows-amd64), const WSAENOPROTOOPT = 10042 #62254