return err
	}
	_, err := fsCall("rename", from, to)
	return err
}

func Truncate(path string, length int64) error {
	if err := checkPath(path); err != nil {
		return err
	}
	_, err := fsCall("truncate", path, length)
	return err
}

func Ftruncate(fd int, length int64) error {
	_, err := fsCall("ftruncate", fd, length)
	return err
}

func Getcwd(buf []byte) (n int, err error) {

//sys	Fchown(fd int, uid int, gid int) (err error) = SYS_FCHOWN32
//sys	Fstat(fd int, stat *Stat_t) (err error) = SYS_FSTAT64
//sys	fstatat(dirfd int, path string, stat *Stat_t, flags int) (err error) = SYS_FSTATAT64
//sys	Ftruncate(fd int, length int64) (err error) = SYS_FTRUNCATE64
//sysnb	Getegid() (egid int) = SYS_GETEGID32
//sysnb	Geteuid() (euid int) = SYS_GETEUID32
//sysnb	Getgid() (gid int) = SYS_GETGID32
//sysnb	Getuid() (uid int) = SYS_GETUID32

		newDirFd,
		newPathPtr,
		newPathLen,
	)
	return errnoErr(errno)
}

func Truncate(path string, length int64) error {
	if path == "" {
		return EINVAL
	}
	fd, err := Open(path, O_WRONLY, 0)
	if err != nil {
		return err
	}
	defer Close(fd)
	return Ftruncate(fd, length)
}

func Ftruncate(fd int, length int64) error {
	errno := fd_filestat_set_size(int32(fd), filesize(length))

//sys	Flock(fd int, how int) (err error)
//sys	Fpathconf(fd int, name int) (val int, err error)
//sys	Fsync(fd int) (err error)
//  Fsync is not called for os.File.Sync(). Please see internal/poll/fd_fsync_darwin.go
//sys	Ftruncate(fd int, length int64) (err error)
//sys	Getdtablesize() (size int)
//sysnb	Getegid() (egid int)
//sysnb	Geteuid() (uid int)
//sysnb	Getgid() (gid int)
//sysnb	Getpgid(pid int) (pgid int, err error)

//sys	Fstatat(fd int, path string, stat *Stat_t, flags int) (err error)
//sys	Fstatvfs1(fd int, buf *Statvfs_t, flags int) (err error) = SYS_FSTATVFS1
//sys	Fsync(fd int) (err error)
//sys	Ftruncate(fd int, length int64) (err error)
//sysnb	Getegid() (egid int)
//sysnb	Geteuid() (uid int)
//sysnb	Getgid() (gid int)
//sysnb	Getpgid(pid int) (pgid int, err error)
//sysnb	Getpgrp() (pgrp int)

//sys	Fstat(fd int, stat *Stat_t) (err error)
//sys	Fstatat(fd int, path string, stat *Stat_t, flags int) (err error)
//sys	Fstatfs(fd int, stat *Statfs_t) (err error)
//sys	Fsync(fd int) (err error)
//sys	Ftruncate(fd int, length int64) (err error)
//sys	Getdents(fd int, buf []byte) (n int, err error)
//sys	Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error)
//sys	Getdtablesize() (size int)
//sysnb	Getegid() (egid int)

//sys	Fstat(fd int, stat *Stat_t) (err error)
//sys	Fstatat(fd int, path string, stat *Stat_t, flags int) (err error)
//sys	Fstatfs(fd int, stat *Statfs_t) (err error)
//sys	Fsync(fd int) (err error)
//sys	Ftruncate(fd int, length int64) (err error)
//sysnb	Getegid() (egid int)
//sysnb	Geteuid() (uid int)
//sysnb	Getgid() (gid int)
//sysnb	Getpgid(pid int) (pgid int, err error)
//sysnb	Getpgrp() (pgrp int)

	if e1 != 0 {
		err = errnoErr(e1)
	}
	return
}

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

func Ftruncate(fd int, length int64) (err error) {
	_, _, e1 := Syscall(SYS_FTRUNCATE64, uintptr(fd), uintptr(length), uintptr(length>>32))
	if e1 != 0 {
		err = errnoErr(e1)
	}
	return
}

	_, _, e1 := Syscall(SYS_FSTATFS, uintptr(fd), uintptr(unsafe.Pointer(buf)), 0)
	if e1 != 0 {
		err = errnoErr(e1)
	}
	return
}

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

func Ftruncate(fd int, length int64) (err error) {
	_, _, e1 := Syscall(SYS_FTRUNCATE, uintptr(fd), uintptr(length), 0)
	if e1 != 0 {
		err = errnoErr(e1)
	}
	return
}

	_, _, e1 := Syscall(SYS_FSTATFS, uintptr(fd), uintptr(unsafe.Pointer(buf)), 0)
	if e1 != 0 {
		err = errnoErr(e1)
	}
	return
}

// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT

func Ftruncate(fd int, length int64) (err error) {
	_, _, e1 := Syscall(SYS_FTRUNCATE, uintptr(fd), uintptr(length), 0)
	if e1 != 0 {
		err = errnoErr(e1)
	}
	return
}