DevToolsmith

Chmod 000

chmod 000 sets the permissions to ---------: it gives nobody any access. Here is exactly what that allows on files and directories, when to use it, and the commands to apply it.

Runs 100% in your browser — nothing is uploaded

ClassreadwriteexecuteValue
owner0
group0
others0
Common:
$ chmod 000 file.sh
$ chmod u=,g=,o= file.sh
  • • The owner can do nothing.
  • • The group can do nothing.
  • • Everyone else can do nothing.

What chmod 000 means

WhoDigitLettersOn a fileOn a directory
owner 0 --- No access No access
group 0 --- No access No access
others 0 --- No access No access

Each digit is the sum of read (4), write (2) and execute (1). In ls -l output it looks like this: 

$ ls -l
----------  1 alice  staff  1834 Oct 21 10:30 example.txt
  • The owner can do nothing.
  • The group can do nothing.
  • Everyone else can do nothing.

When to use 000

  • Temporarily disabling a file
  • Testing permission errors

No user except root can read, write or execute the file. It is a quick way to disable a config or script without deleting it, and handy for testing how your code handles “Permission denied”. Root ignores the mode, so it doesn’t hide anything from administrators.

Is chmod 000 safe?

Yes. Nobody outside the owner can access it at all (except root).

Commands

# One file
chmod 000 file

# Same thing in symbolic form
chmod u=,g=,o= file

# Every file under a tree (leaves directories alone)
find /path/to/dir -type f -exec chmod 000 {} +

# Check the result
stat -c '%a %A %n' file    # Linux
stat -f '%Lp %Sp %N' file  # macOS

Avoid chmod -R 000 on a whole tree: it gives files and directories the same mode. The find form above changes only files.

Compare with similar modes

ModeSymbolicDifference
700 rwx------ Gives the owner full access and everyone else nothing
600 rw------- Lets only the owner read and write
500 r-x------ Lets only the owner read and execute
400 r-------- Lets only the owner read

Other chmod values

777 · 775 · 770 · 755 · 751 · 750 · 744 · 711 · 700 · 666 · 664 · 660 · 644 · 640 · 600 · 555 · 500 · 444 · 400 · 1777 · 2775 · 4755

Need a different combination? Use the Chmod Calculator.

Sources

Spotted a mistake? Email hello@devtoolsmith.com and we’ll fix it.

Frequently asked questions

What does chmod 000 mean?

chmod 000 sets the permissions to ---------. The owner can do nothing. The group can do nothing. Everyone else can do nothing.

Is chmod 000 safe?

Yes. Nobody outside the owner can access it at all (except root).