chmod 063 Permission Explained
Summary: chmod 063 gives the owner no access, the group read/write, and everyone else write/execute.
| Class | Read (4) | Write (2) | Execute (1) | Octal |
|---|---|---|---|---|
| Owner (u) | 0 | |||
| Group (g) | 6 | |||
| Others (o) | 3 |
chmod 063 filename
chmod 063 Breakdown
| Class | Digit | Symbolic | On a file | On a directory |
|---|---|---|---|---|
| Owner (u) | 0 |
--- |
No access | Cannot list, enter, or modify |
| Group (g) | 6 |
rw- |
Read and write | Can list names, cannot enter |
| Others (o) | 3 |
-wx |
Write and execute | Can enter and create/delete files, but not list |
Is chmod 063 Safe?
Critical Risk
- Anyone on the system can modify or replace this file.
- 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
063 is uncommon in standard Linux setups. The closest widely used permission is chmod 666.
chmod 063 Command Examples
# Apply using octal mode
chmod 063 filename
# Apply using equivalent symbolic mode
chmod u=,g=rw,o=wx filename
# Recursive command warning:
chmod -R 063 /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 063 {} +
# Verify permissions
stat -c '%a %A %n' filename # Linux
stat -f '%Lp %Sp %N' filename # macOS
# Example ls -l output:
----rw--wx 1 alice staff 1024 Jan 15 10:00 example.txtumask Relationship
A umask of 714 makes new directories 063. Test umask values with our interactive Umask Calculator.
Frequently Asked Questions
What does chmod 063 mean?
chmod 063 gives the owner no access, the group read/write, and everyone else write/execute. In octal notation, the owner receives 0 (no access), the group receives 6 (read/write), and others receive 3 (write/execute).
Is chmod 063 safe?
chmod 063 is classified as Critical Risk. Anyone on the system can modify or replace this file.
What is chmod 063 in symbolic notation?
In symbolic notation, chmod 063 is represented as ---rw--wx. You can apply this permission using the equivalent symbolic command "chmod u=,g=rw,o=wx filename".
Related Permissions
Change one bit: