chmod 030 Permission Explained
Summary: chmod 030 gives the owner no access, the group write/execute, and everyone else no access.
| Class | Read (4) | Write (2) | Execute (1) | Octal |
|---|---|---|---|---|
| Owner (u) | 0 | |||
| Group (g) | 3 | |||
| Others (o) | 0 |
chmod 030 filename
chmod 030 Breakdown
| Class | Digit | Symbolic | On a file | On a directory |
|---|---|---|---|---|
| Owner (u) | 0 |
--- |
No access | Cannot list, enter, or modify |
| Group (g) | 3 |
-wx |
Write and execute | Can enter and create/delete files, but not list |
| Others (o) | 0 |
--- |
No access | Cannot list, enter, or modify |
Is chmod 030 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
030 is uncommon in standard Linux setups. The closest widely used permission is chmod 000.
chmod 030 Command Examples
# Apply using octal mode
chmod 030 filename
# Apply using equivalent symbolic mode
chmod u=,g=wx,o= filename
# Recursive command warning:
chmod -R 030 /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 030 {} +
# Verify permissions
stat -c '%a %A %n' filename # Linux
stat -f '%Lp %Sp %N' filename # macOS
# Example ls -l output:
-----wx--- 1 alice staff 1024 Jan 15 10:00 example.txtumask Relationship
A umask of 747 makes new directories 030. Test umask values with our interactive Umask Calculator.
Frequently Asked Questions
What does chmod 030 mean?
chmod 030 gives the owner no access, the group write/execute, and everyone else no access. In octal notation, the owner receives 0 (no access), the group receives 3 (write/execute), and others receive 0 (no access).
Is chmod 030 safe?
chmod 030 is classified as Moderate. Every member of the group can modify this file.
What is chmod 030 in symbolic notation?
In symbolic notation, chmod 030 is represented as ----wx---. You can apply this permission using the equivalent symbolic command "chmod u=,g=wx,o= filename".
Related Permissions
Change one bit: