Linux Chmod: how to Change the Permissions, Owner, And Group of a File

Linux Chmod: Change the Permissions, Owner, And Group of a File.

For those website owners who often open a website using cpanel, or you are accustomed to using the Linux operating system (also read: understanding linux) may already be familiar with this chmod term. Well in this occasion we will discuss a little bit permissions or privileges that normally found in chmod (Change Mode) is.

Chmod

Chmod stands for change mode is used to add and subtract users permission to access files or directories, can also use a numeric system of coding or letter coding system.

The command used to change file permissions is chmod. Chmod command can be used to add, delete, or to modify the permissions of the file or directoty. Use the + sign to add a permission, or mark - to remove a permission. Here are some options that can be used with the chmod command.

There are three kinds of permissions or licensing that can be changed are:

-r: to read.

-w: to write.

-x: to execute.

numeric information from a file permision:

0 = no operation is permitted (null / hidden).
1 = excuse for allowing to carry out the execution (execute)
2 = numeric value by allowing for writing. (Write)
4 = numeric value to allow for reading. (Read)

each file / directory has three structures in the permitting / file permissions, ie for the owner, group, and user.

To make restrictions on a file,
we have to make an excuse the file by setting the "CHMOD" to be the material of the web we can be protected and properly arranged. Here is an example:

Suppose that the directory "home" we have the default permissions 711 then it means:

7 = 4 + 2 + 1: Companions (owner / owner / admin) are allowed to read, write and execute files / directories.
1 = 1: all users in the group friend is only allowed to execute the action but were not allowed to read and write. file / directory.
1 = 1: all user is not a friend of the group can execute but not read and write files / directories.

Suppose we have a public_html directory permissions 755 means:

7 = 4 + 2 + 1: Companions (owner / owner / admin) are allowed to read, write and execute files / directories.
5 = 4 + 1: all users in the group is only allowed membac friend and did not execute but dipekenankan to write.
5 = 4 + 1: all the user instead of the group companions allowed to read and execute actions but are not allowed to write.

Files companions to public_html directory permissions should at least have a value to the file is
644 (and its directory is the directory to be 755), or WWW server will not be able to read it so that the weblog will not appear on the web browser window.

Chmod Value for the permissions file "index html" is = 644

Value chmod to make the images directory and file contents can be read by all users, namely:

chmod value: 755 to file images

chmod value: 644 Directory image

for hidden clicking a file then:

chmod 700 filename

chmod diagram
chmod diagram
Note: The CHMOD can be set in the page file on the ftp client manager, to be more easily able to use the facilities ftp client software such as FileZilla, SmartFTP and so forth.

Source: https://en.wikipedia.org/wiki/Chmod