How to create a hidden file in Windows/Mac/Linux?

Question

I build an console application, need create some hidden files. As well I know filename start with dot will hidden in Linux and mac, but windows?

Set file attributes?

Is there a way to create hidden files and directories in both Windows / Linux / Mac?

Cushman

Possible duplicate of How can I make a file hidden on Windows?, How to create hidden files in Linux?, How to create a hidden file in any OS using Java and friends. – Mediatize

Answer 1

Windows:

SetFileAttributesW function

Sets the attributes for a file or directory.

FILE_ATTRIBUTE_HIDDEN 2 (0x2)

The file or directory is hidden. It is not included in an ordinary directory listing.

---

Go:

Package syscall

func SetFileAttributes

func SetFileAttributes(name *uint16, attrs uint32) (err error)

---

Convert from a Go UTF-8 encoded string (string) to a Windows UTF-16 encoded string pointer (*uint16).

Package syscall

func UTF16PtrFromString

func UTF16PtrFromString(s string) (*uint16, error)

UTF16PtrFromString returns pointer to the UTF-16 encoding of the UTF-8 string s, with a terminating NUL added. If s contains a NUL byte at any location, it returns (nil, EINVAL).

---

Use OS Build Contraints.

---

For example,

hide/attrib.go:

package main

import (
    "fmt"
    "io/ioutil"
    "os"
)

func main() {
    filename := `test.hidden.file`
    os.Remove(filename)
    os.Remove("." + filename)
    err := ioutil.WriteFile(filename, []byte(filename), 0666)
    if err != nil {
        fmt.Fprintln(os.Stderr, err)
        return
    }
    err = HideFile(filename)
    if err != nil {
        fmt.Fprintln(os.Stderr, err)
        return
    }
    fmt.Println("hidden:", filename)
}

hide/hide.go:

// +build !windows

package main

import (
    "os"
    "path/filepath"
    "strings"
)

func HideFile(filename string) error {
    if !strings.HasPrefix(filepath.Base(filename), ".") {
        err := os.Rename(filename, "."+filename)
        if err != nil {
            return err
        }
    }
    return nil
}

hide/hide_windows.go:

// +build windows

package main

import (
    "syscall"
)

func HideFile(filename string) error {
    filenameW, err := syscall.UTF16PtrFromString(filename)
    if err != nil {
        return err
    }
    err = syscall.SetFileAttributes(filenameW, syscall.FILE_ATTRIBUTE_HIDDEN)
    if err != nil {
        return err
    }
    return nil
}

Output (Linux):

$ tree hide
hide
├── attrib.go
├── hide.go
└── hide_windows.go
$

$ go build && ./hide
hidden: test.hidden.file
$ ls -a .test.hidden.file
.test.hidden.file
$ 

Output (Windows):

>go build && hide
hidden: test.hidden.file
>attrib test.hidden.file
A   H        \test.hidden.file
>

Hypogeal

This code can't build on linux. err: undefined: syscall.SetFileAttributes – Cushman

if runtime.GOOS == "windows" { filenameW, err := syscall.UTF16PtrFromString(filename) if err != nil { return false, err } err = syscall.SetFileAttributes(filenameW, syscall.FILE_ATTRIBUTE_HIDDEN) if err != nil { return false, err } } – Cushman

@steve: You didn't implement build constraints. See my revised example. – Hypogeal

Answer 2

I made a cross-platform module for this (it's available here: higgs). You can hide or unhide file or directory simply by calling Hide or Unhide functions.

Sample code:

package main

import (
    "fmt"
    "github.com/dastoori/higgs"
)

func main() {
    err := higgs.Hide("foo.txt")
    
    if err != nil {
        fmt.Println(err)
    }
}

Ivories

Answer 3

Make a file like this:

//go:generate mkwinsyscall -output zhide.go hide.go
//sys setFileAttributes(name string, attr int) (err error) = kernel32.SetFileAttributesW
package main

const (
   file_attribute_hidden = 2
   file_attribute_normal = 128
)

func main() {
   setFileAttributes("file.txt", file_attribute_hidden)
}

Then build:

go mod init hide
go mod tidy
go generate
go build

Gorman

Answer 4

import (
    _ "golang.org/x/sys/windows"
    "os"
    "runtime"
    "syscall"
)

func HideFile(filename string) (status bool, err error) {
    if runtime.GOOS == "windows" {
        filenameW, err := syscall.UTF16PtrFromString(filename)
        if err != nil {
            return false, err
        }

        err = syscall.SetFileAttributes(filenameW, syscall.FILE_ATTRIBUTE_HIDDEN)
        if err != nil {
            return false, err
        }
    } else {
        if filename[0:1] != "." {
            err = os.Rename(filename, "." + filename)
            if err != nil {
                return false, err
            }
        }
    }

    return true, nil
}

That's my code. But can't build in Linux。

Errors:

src/util/hidden.go:12:21: undefined: syscall.UTF16PtrFromString
src/util/hidden.go:17:9: undefined: syscall.SetFileAttributes
src/util/hidden.go:17:46: undefined: syscall.FILE_ATTRIBUTE_HIDDEN

Cushman

You didn't implement build constraints. See my revised example. – Hypogeal