File permissions·745
745
rwxr--r-x
-rwxr--r-x

chmod 745 — the rwxr--r-x permission

745 is rwxr--r-x. The owner gets rwx, and everyone else gets rx.

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
Owner7
Group4··
Others5·

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
rwxr--r-x
ls -l (file)
-rwxr--r-x
ls -l (directory)
drwxr--r-x
chmod symbolic form
chmod u=rwx,g=r,o=rx
Command
chmod 745 <file>
Binary
111100101
Decimal
485
umask (directory)
032
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 745 mean?

It is rwxr--r-x. ls -l shows a file as -rwxr--r-x and a directory as drwxr--r-x.

Q. How is 745 written in rwx form?

It is the same as chmod u=rwx,g=r,o=rx.

Q. What can other people do with 745?

They get r-x.

Q. Which umask produces 745?

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