User Tools

Site Tools


os_cp:users_permissions

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Next revision
Previous revision
os_cp:users_permissions [2023/04/02 11:10]
jkonczak utworzono
os_cp:users_permissions [2024/03/19 15:54] (current)
jkonczak [Users and groups]
Line 4: Line 4:
 A user is identified by a numerical __u__ser __id__entifier – **uid**. Uids are mapped to usernames. A user is identified by a numerical __u__ser __id__entifier – **uid**. Uids are mapped to usernames.
 \\ \\
-A group is identified by a numerical __g__roup __id__entifier – **uid**, that are likewise mapped to group names.+A group is identified by a numerical __g__roup __id__entifier – **gid**, that are likewise mapped to group names.
  
 A user must be in one primary group and can be in multiple supplementary groups. A user must be in one primary group and can be in multiple supplementary groups.
Line 30: Line 30:
 <​html></​small></​html>​ <​html></​small></​html>​
  
-The user whose uid equals **0** is referred to as **superuser**. Traditional username of the superuser is **[[https://​pl.wikipedia.org/​wiki/​Root|root]]**.+The user whose uid equals **0** is referred to as **superuser**. Traditional username of the superuser is **[[https://​en.wikipedia.org/​wiki/​Superuser|root]]**.
  
 To check who you are, you can run the ''​**whoami**''​ command. \\ To check who you are, you can run the ''​**whoami**''​ command. \\
Line 129: Line 129:
 \\ \\
 <​small>​Additionally,​ there are three other special permissions:​ set-user-id (suid, __**s**__), set-group-id (sgid, __**s**__) and sticky (__**t**__).</​small>​ <​small>​Additionally,​ there are three other special permissions:​ set-user-id (suid, __**s**__), set-group-id (sgid, __**s**__) and sticky (__**t**__).</​small>​
 +
 +Upon file access, when the file belongs to the current user, only user's permissions are considered.\\
 +If the file does not belong to the user but the user belongs to the file's group, only group'​s permissions are considered.\\
 +If the file does not belong to the user and the user does not belong to the file's group, only others'​ permission are considered.\\
 +<​small>​Note that if a file has read permission for the group but no read permission for the user, then the owner cannot display the file even if the owner belongs to the file's group.</​small>​
  
 The execute mode for files stands for running them (e.g., as a program or a script), for directories – entering it. The execute mode for files stands for running them (e.g., as a program or a script), for directories – entering it.
os_cp/users_permissions.1680426650.txt.gz · Last modified: 2023/04/02 11:10 by jkonczak