Notation *

* symbolic notation


chmod ?

chmod is the command and system call, in Unix-like operating systems,which may change the access permissions to file system objects (files and folders).

chmod 755 /var/example/ will set 755 (drwxr-xr-x) on /var/example/

chmod -R 755 /var/example/ will set 755 (drwxr-xr-x) recursively on /var/example/ and his content.

Want to know more about chmod ?

Take a look on wikipedia.org / Chmod or, on you system chmod --helpman chmod

How to know the rights of file or a folder ?

Use the ls command.

ls -l /var/list all files and directory in /var/, the -l is to show rights, weight (...) and others informations.

Take a look on the help or the manual for more informations (RTFM).ls --helpman ls

This tools is really complete ?

Nope, not really, there are some options to chmod we didn't see with this tool. For more information, you can check some good source like
wikipedia.org / Chmod, wikipedia.org / File_system_permissions

can there be more than 3 digits ?

Yep, there may be one other digits coming first, like 755 become 0755. Depends of sticky, SUID -setuid- and GUID -setgid-, take a look on the next point of this FAQ.

There is some other letters than xrc ?

Yep, there may be other letters when you look at the rights of your files and folders.

  • The first letter, other than -
    • d--------- is for a Directory.
    • l--------- is for a symbolic Link.
    • c--------- is for a Character special file.
    • b--------- is for a Block special file.
    • p--------- is for a FIFO (Pipe).
    • s--------- is for a Socket.
  • ---------t---------T Sticky Bit, short story, this right disallow any right to delete a file, wathever the parent directory rights, if the user who want to delete the file is not root or the owner of the file. wikipedia.org / Sticky_bit.
  • ---s---------S------------s---------S--- are about SUID -setuid- and GUID -setgid-, this are some specifics rights allowing to "bypass" some rights with the rights of a the owner or the group. Take a look at wikipedia.org / Setuid for a better explanations.

Other great tools, free and beautiful.



Test your Internet connection (ping, lag, micro-break ...)

YouTube thumbnails

YouTube Miniatures

Get thumbnails of a YouTube video



Generate UUID version 4 (Universal Unique Identifier)



chmod, for the right rights