POSIXõigused

POSIXõigused, often translated as POSIX permissions, are a fundamental access control mechanism in Unix-like operating systems, including Linux and macOS. They are defined by the Portable Operating System Interface (POSIX) standard. These permissions govern which users can perform specific actions on files and directories.

There are three basic types of permissions: read (r), write (w), and execute (x). Each permission can be applied to three distinct categories of users: the owner of the file, members of the group associated with the file, and others (everyone else). The owner is the user who created the file. The group is a collection of users who can share access to files. Others represent all users not included in the owner or group categories.

These permissions are typically represented in a ten-character string. The first character indicates the file type (e.g., a hyphen for a regular file, 'd' for a directory). The subsequent nine characters are divided into three sets of three, representing the owner, group, and others permissions respectively. For example, a string like -rwxr-xr-- means a regular file where the owner has read, write, and execute permissions, the group has read and execute permissions, and others have only read permission.

The `chmod` command is used to change these permissions, while the `ls -l` command is used to view them. Understanding POSIX permissions is crucial for system administration and secure file management in Unix-like environments.