}

			if opts.NoDelay {
				_ = syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, unix.TCP_NODELAY, 1)
				_ = syscall.SetsockoptInt(fd, syscall.SOL_TCP, unix.TCP_CORK, 0)
			}

			// Enable TCP open
			// https://lwn.net/Articles/508865/ - 32k queue size.
			_ = syscall.SetsockoptInt(fd, syscall.SOL_TCP, unix.TCP_FASTOPEN, 32*1024)

			// Enable TCP fast connect

func dangerousSlice(t *testing.T) []byte {
	pagesize := syscall.Getpagesize()
	b, err := syscall.Mmap(0, 0, 3*pagesize, syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_ANONYMOUS|syscall.MAP_PRIVATE)
	if err != nil {
		t.Fatalf("mmap failed %s", err)
	}
	err = syscall.Mprotect(b[:pagesize], syscall.PROT_NONE)
	if err != nil {
		t.Fatalf("mprotect low failed %s\n", err)
	}
	err = syscall.Mprotect(b[2*pagesize:], syscall.PROT_NONE)

		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 http

import (
	"context"
	"net"
	"syscall"
	"time"
)

// TODO: if possible implement for non-linux platforms, not a priority at the moment
//
//nolint:unused
func setTCPParametersFn(opts TCPOptions) func(network, address string, c syscall.RawConn) error {
	return func(network, address string, c syscall.RawConn) error {
		return nil
	}
}

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package disk

import (
	"errors"
	"fmt"
	"syscall"
)

// GetInfo returns total and free bytes available in a directory, e.g. `/`.
func GetInfo(path string, _ bool) (info Info, err error) {
	s := syscall.Statfs_t{}
	err = syscall.Statfs(path, &s)
	if err != nil {
		return Info{}, err
	}
	reservedBlocks := s.Bfree - uint64(s.Bavail)
	info = Info{

	if !ok {
		return "UNKNOWN"
	}
	return fsTypeString
}

// GetInfo returns total and free bytes available in a directory, e.g. `/`.
func GetInfo(path string, _ bool) (info Info, err error) {
	s := syscall.Statfs_t{}
	err = syscall.Statfs(path, &s)
	if err != nil {
		return Info{}, err
	}
	reservedBlocks := s.Bfree - s.Bavail
	info = Info{
		Total:  uint64(s.Frsize) * (s.Blocks - reservedBlocks),

	if e, ok := err.(Err); ok {
		return e
	}

	// Show a generic message for known golang errors
	if errors.Is(err, syscall.EADDRINUSE) {
		return ErrPortAlreadyInUse(err).Msg("Specified port is already in use")
	} else if errors.Is(err, syscall.EACCES) || errors.Is(err, syscall.EPERM) {
		if netErr, ok := err.(*net.OpError); ok {
			return ErrPortAccess(netErr).Msg("Insufficient permissions to use specified port")
		}