File permissions·061
061
---rw---x
----rw---x

chmod 061 — the ---rw---x permission

061 is ---rw---x. The owner can do nothing, and everyone else gets x.

Who can do what

Three rows for owner, group and others; three columns for read, write and execute. On a folder that last one means the right to go inside.

ReadWriteExecute
Owner0···
Group6·
Others1··

On a folder the execute bit means going inside. With read but no execute you can list the names yet open nothing in it.

Symbolic
---rw---x
ls -l (file)
----rw---x
ls -l (directory)
d---rw---x
chmod symbolic form
chmod u=,g=rw,o=x
Command
chmod 061 <file>
Binary
000110001
Decimal
49
umask (directory)
716
umask (file)
Not reachable — new files never start with the execute bit

One digit away

How to read this

  • Read is 4, write 2, execute 1; add them for one digit. 7 is 4+2+1, 5 is 4+1.
  • The digits are owner, group, others, left to right.
  • umask is what gets taken away: from 777 for directories, from 666 for files.
  • Special bits (setuid 4000, setgid 2000, sticky 1000) add a fourth digit in front — /tmp is 1777.

Frequently asked questions

Q. What does chmod 061 mean?

It is ---rw---x. ls -l shows a file as ----rw---x and a directory as d---rw---x.

Q. How is 061 written in rwx form?

It is the same as chmod u=,g=rw,o=x.

Q. What can other people do with 061?

They get --x.

Q. Which umask produces 061?

716 for directories. For files it cannot be reached by umask alone, since new files never carry the execute bit.