[]int{4, 2, 1, 3, 0},                // Perm(5)
	[]int{0, 2, 3, 1, 5, 4, 6, 7},       // Perm(8)
	[]int{2, 0, 8, 3, 4, 7, 6, 5, 1},    // Perm(9)
	[]int{0, 6, 5, 3, 8, 4, 1, 2, 9, 7}, // Perm(10)
	[]int{9, 14, 4, 11, 13, 8, 0, 6, 2, 12, 3, 7, 1, 10, 5, 15}, // Perm(16)
	[]int{},                             // Perm(0)
	[]int{0},                            // Perm(1)
	[]int{2, 4, 0, 3, 1},                // Perm(5)

#include <sys/mman.h>
#include <sys/thread.h>
#include <sys/resource.h>

#include <unistd.h>
#include <fcntl.h>
#include <pthread.h>
#include <semaphore.h>
*/
import "C"

const (
	_EPERM     = C.EPERM
	_ENOENT    = C.ENOENT
	_EINTR     = C.EINTR
	_EAGAIN    = C.EAGAIN
	_ENOMEM    = C.ENOMEM
	_EACCES    = C.EACCES
	_EFAULT    = C.EFAULT
	_EINVAL    = C.EINVAL
	_ETIMEDOUT = C.ETIMEDOUT

	VX     d3, d1, d1  \
	VERLLF $7, a1, a1  \
	VERLLF $7, b1, b1  \
	VERLLF $7, c1, c1  \
	VERLLF $7, d1, d1

#define PERMUTE(mask, v0, v1, v2, v3) \
	VPERM v0, v0, mask, v0 \
	VPERM v1, v1, mask, v1 \
	VPERM v2, v2, mask, v2 \
	VPERM v3, v3, mask, v3

#define ADDV(x, v0, v1, v2, v3) \
	VAF x, v0, v0 \
	VAF x, v1, v1 \
	VAF x, v2, v2 \
	VAF x, v3, v3

			// See issue #42334.
			//
			// If the file is on NFS, we can see EOPNOTSUPP.
			// See issue #40731.
			//
			// If the process is running inside a Docker container,
			// we might see EPERM instead of ENOSYS. See issue
			// #40893. Since EPERM might also be a legitimate error,
			// don't mark copy_file_range(2) as unsupported.
			return 0, false, nil
		case nil:
			if n == 0 {
				// If we did not read any bytes at all,

// for os.OpenFile().
func LockedOpenFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {
	return lockedOpenFile(path, flag, perm, syscall.F_SETLKW)
}

// Open - Call os.OpenFile
func Open(path string, flag int, perm os.FileMode) (*os.File, error) {
	return os.OpenFile(path, flag, perm)

	Open(name string) (*os.File, error)
	OpenFile(name string, flag int, perm os.FileMode) (*os.File, error)
	Rename(oldpath, newpath string) error
}

// RealOS is used to dispatch the real system level operations.
type RealOS struct{}

// MkdirAll will call os.MkdirAll to create a directory.
func (RealOS) MkdirAll(path string, perm os.FileMode) error {
	return os.MkdirAll(path, perm)
}

// Symlink will call os.Symlink to create a symbolic link.

		 *
		 * Linux will still error if we ask for user attributes on a file that
		 * we don't have read permissions on, so don't ignore those errors
		 */
		if e != nil {
			if e == EPERM && nsid != EXTATTR_NAMESPACE_USER {
				continue
			}
			return s, e
		}

		s += stmp
		pos = s
		if pos > destsiz {
			pos = destsiz
		}
	}

	return s, nil
}

			if op, ok := err.(*net.OpError); ok {
				err = op.Err
			}
			if sys, ok := err.(*os.SyscallError); ok {
				err = sys.Err
			}
			switch err {
			case syscall.EPERM, syscall.EINVAL:
			default:
				t.Fatalf("WriteMsgUnix failed with %v, want EPERM or EINVAL", err)
			}
		}

		ucred.Pid = int32(os.Getpid())
		ucred.Uid = uint32(os.Getuid())
		ucred.Gid = uint32(os.Getgid())
		oob := syscall.UnixCredentials(&ucred)

* All changes should have an associated GitHub issue and/or a release note.
* Large fixes, where the LOC>100 not withstanding unit tests changes, require subject matter expert approval.

# Backporting fixes

* Cherry-picking is discussed in the original PR and subject-matter experts have approved the backport.

		return nil
	case EAGAIN:
		return errEAGAIN
	case EINVAL:
		return errEINVAL
	case ENOENT:
		return errENOENT
	}
	return e
}

var errnoByCode = map[string]Errno{
	"EPERM":           EPERM,
	"ENOENT":          ENOENT,
	"ESRCH":           ESRCH,
	"EINTR":           EINTR,
	"EIO":             EIO,
	"ENXIO":           ENXIO,
	"E2BIG":           E2BIG,
	"ENOEXEC":         ENOEXEC,