Understanding Linux File Permissions :Basic File Permissions
Each file and directory has three user based permission groups:
owner - The Owner permissions apply only the owner of the file or directory, they will not impact the actions of other users.
group - The Group permissions apply only to the group that has been assigned to the file or directory, they will not effect the actions of other users.
all users - The All Users permissions apply to all other users on the system, this is the permission group that you want to watch the most.
Each file or directory has three basic permission types:
read - The Read permission refers to a user's capability to read the contents of the file.
write - The Write permissions refer to a user's capability to write or modify a file or directory.
execute - The Execute permission affects a user's capability to execute a file or view the contents of a directory
Command to viewing the permissions : "ls -l"
The permission in the command line is displayed as: _rwxrwxrwx 1 owner:group
The first character that I marked with an underscore is the special permission flag that can vary.
First set ( three characters ) : owner permissions.
Second set ( three characters ) : Group permissions.
Third set (three characters ) : All Users permissions.
Following that grouping since the integer/number displays the number of hardlinks to the file.
The last piece is the Owner and Group assignment formatted as Owner:Group.
Modify Permissions Command : chmod
The Permission Groups used are:
Assignment Operators are + (plus) and - (minus); these are used to tell the system whether to add or remove the specific permissions.
The Permission Types that are used are:
To make this modification you would invoke the command: chmod a-rw file1
To add the permissions above you would invoke the command: chmod a+rw file1
Using Binary References to Set permissions :
For example : chmod 640 file1, which means
owner : read and write permissions
group : read permissions,
all other user : no rights to the file.
Representation of numbers in permission :
First number represents : Owner permission
Second represents : Group permissions
Last number represents : permissions for all other users.
The numbers are a binary representation of the rwx string.
So to set a file to permissions on file1 to read _rwxr_____, you would enter chmod 740 file1.
pixelskylines
ellievsbear
kaledo-art
turnnoffyourmind
blakekathryn