chmod 020 Permission Explained
Summary: chmod 020 gives the owner no access, the group write, and everyone else no access.
| Class | Read (4) | Write (2) | Execute (1) | Octal |
|---|---|---|---|---|
| Owner (u) | 0 | |||
| Group (g) | 2 | |||
| Others (o) | 0 |
chmod 020 filename
chmod 020 Breakdown
| Class | Digit | Symbolic | On a file | On a directory |
|---|---|---|---|---|
| Owner (u) | 0 |
--- |
No access | Cannot list, enter, or modify |
| Group (g) | 2 |
-w- |
Write only (rarely useful) | No practical effect without x |
| Others (o) | 0 |
--- |
No access | Cannot list, enter, or modify |
Is chmod 020 Safe?
Moderate
- Every member of the group can modify this file.
- Even the owner cannot modify this file without changing permissions first.
- Unusual: a lower class has permissions the class above it lacks.
Common Use Cases
020 is uncommon in standard Linux setups. The closest widely used permission is chmod 000.
chmod 020 Command Examples
# Apply using octal mode
chmod 020 filename
# Apply using equivalent symbolic mode
chmod u=,g=w,o= filename
# Recursive command warning:
chmod -R 020 /path/to/dir
# Note: -R applies the same mode to files and directories. Use find to treat them separately:
find /path/to/dir -type f -exec chmod 020 {} +
# Verify permissions
stat -c '%a %A %n' filename # Linux
stat -f '%Lp %Sp %N' filename # macOS
# Example ls -l output:
-----w---- 1 alice staff 1024 Jan 15 10:00 example.txtumask Relationship
A umask of 757 makes new directories 020 and new files 020. Test umask values with our interactive Umask Calculator.
Frequently Asked Questions
What does chmod 020 mean?
chmod 020 gives the owner no access, the group write, and everyone else no access. In octal notation, the owner receives 0 (no access), the group receives 2 (write), and others receive 0 (no access).
Is chmod 020 safe?
chmod 020 is classified as Moderate. Every member of the group can modify this file.
What is chmod 020 in symbolic notation?
In symbolic notation, chmod 020 is represented as ----w----. You can apply this permission using the equivalent symbolic command "chmod u=,g=w,o= filename".
Related Permissions
Change one bit: