File Permission Modes

File Permission Modes
  7       5     5
 user   group  world
 r+w+x  r+x    r+x
 4+2+1  4+0+1  4+0+1  = 755

The permission mode is computed by adding up the following values for the user, the file group, and for everyone else. The diagram shows how.

  • Read 4 – Allowed to read files
  • Write 2 – Allowed to write/modify files
  • eXecute 1 – Read/write/delete/modify/directory
  7       4      4
 user   group  world
 r+w+x    r      r
 4+2+1  4+0+0  4+0+0  = 744

Example Permission Modes

Mode Str Perms Explanation
0477 -r–rwxrwx owner has read only (4), other and group has rwx (7)
0677 -rw-rwxrwx owner has rw only(6), other and group has rwx (7)
0444 -r–r–r– all have read only (4)
0666 -rw-rw-rw- all have rw only (6)
0400 -r——– owner has read only(4), group and others have no permission(0)
0600 -rw——- owner has rw only, group and others have no permission
0470 -r–rwx— owner has read only, group has rwx, others have no permission
0407 -r—–rwx owner has read only, other has rwx, group has no permission
0670 -rw-rwx— owner has rw only, group has rwx, others have no permission
0607 -rw—-rwx owner has rw only, group has no permission and others have rwx
See full list 0000 to 0777.

View Permissions, Users, and Group

To view the permissions and who the user owner is type in the following command in terminal:

ls -l

This will give you the results in the image below. (notes have been added to describe what each column is for.

fig_permissions

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