chmod 643 Permission Explained
Summary: chmod 643 gives the owner read/write, the group read, and everyone else write/execute.
| Class | Read (4) | Write (2) | Execute (1) | Octal |
|---|---|---|---|---|
| Owner (u) | 6 | |||
| Group (g) | 4 | |||
| Others (o) | 3 |
chmod 643 filename
chmod 643 Breakdown
| Class | Digit | Symbolic | On a file | On a directory |
|---|---|---|---|---|
| Owner (u) | 6 |
rw- |
Read and write | Can list names, cannot enter |
| Group (g) | 4 |
r-- |
Read only | Can list names, but not enter |
| Others (o) | 3 |
-wx |
Write and execute | Can enter and create/delete files, but not list |
Is chmod 643 Safe?
Critical Risk
- Anyone on the system can modify or replace this file.
- Unusual: a lower class has permissions the class above it lacks.
Common Use Cases
643 is uncommon in standard Linux setups. The closest widely used permission is chmod 640.
chmod 643 Command Examples
# Apply using octal mode
chmod 643 filename
# Apply using equivalent symbolic mode
chmod u=rw,g=r,o=wx filename
# Recursive command warning:
chmod -R 643 /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 643 {} +
# Verify permissions
stat -c '%a %A %n' filename # Linux
stat -f '%Lp %Sp %N' filename # macOS
# Example ls -l output:
-rw-r---wx 1 alice staff 1024 Jan 15 10:00 example.txtumask Relationship
A umask of 134 makes new directories 643. Test umask values with our interactive Umask Calculator.
Frequently Asked Questions
What does chmod 643 mean?
chmod 643 gives the owner read/write, the group read, and everyone else write/execute. In octal notation, the owner receives 6 (read/write), the group receives 4 (read), and others receive 3 (write/execute).
Is chmod 643 safe?
chmod 643 is classified as Critical Risk. Anyone on the system can modify or replace this file.
What is chmod 643 in symbolic notation?
In symbolic notation, chmod 643 is represented as rw-r---wx. You can apply this permission using the equivalent symbolic command "chmod u=rw,g=r,o=wx filename".
Related Permissions
Change one bit: