Setting Default permissions of files and directories in linux

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Each file on the system has a set of permissions that determine which users can access the files and what type of access they have.

When you create a file/directory in Linux, it gets the default permissions set by the system administrator.

For example, when I created a file in Linux, I got permissions: '0664'
When creating a directory, the permissions in my system are: '0775'


File creation mask determines default permissions. If no mask were used the permissions would be:

  • 666 for files
  • 777 for directories
File creation mask is set by system administrators. To set this mask or know the current mask, 'umask' command is used.

Running 'umask' without any arguments will show the current mask.

To set filemask: 'umask <octal value of permissions> or 'umask -S <symbolic notation>'

The permissions of file will be : Base Permission (0666) - umask value(0002) in my case = (0664)

The permissions of directory will be : Base Permission (0777) - umask value(0002) in my case = (0775)


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