Chmod 1700 Explained
Chmod 1700: sticky bit with owner-only access. Protects against deletion in owner-only directories. A specialized hardened permission.
Permission
1700
rwx-----T
chmod 1700 filename
Permission Breakdown
| Role | Read (4) | Write (2) | Execute (1) | Octal | Meaning |
|---|---|---|---|---|---|
| Owner | r | w | x | 7 | read, write, execute |
| Group | - | - | - | 0 | no permissions |
| Others | - | - | - | 0 | no permissions |
Visual Permission Grid
Detailed Explanation
The permission 1700 sets the sticky bit on a directory where only the owner has access.
Octal breakdown:
- 1 (Special): sticky bit set
- 7 (Owner): read (4) + write (2) + execute (1) = full access
- 0 (Group): no access
- 0 (Others): no access
In symbolic notation this is rwx-----T. The uppercase T indicates that the sticky bit is set but the execute bit for others is not set. Only the owner can access the directory.
The sticky bit on a directory that only the owner can access is somewhat redundant, since only the owner can interact with files in the directory anyway. However, it may serve as an extra precaution in environments where permissions might be changed later, or as a security policy compliance measure.
Use Case
Used as a hardened default for private directories where the sticky bit serves as a defense-in-depth measure, ensuring file deletion protection even if permissions are later relaxed.