26. How to find out the current working directory? - ll; - who; - uname -a; - pwd; 27. On the server, there is a directory containing a subdirectory, which in turn contains a file. You are the owner of everything recursively (/dir/dir/file), and the group is also yours. If you try to read the file with your user, the console returns a permission denied message. What is missing? - The x bit in one of the directories; - Root user rights; - Read permission for the file; - Possibly only if the file is executable; 28. What data streams do you know in Linux?

26. The current working directory can be found using the command pwd (print working directory). It outputs the full path to the directory you are currently in.

• ll — this command provides a detailed list of files in the directory.
• who — shows who is currently logged into the system.
• uname -a — displays system information.

27. If you get "permission denied" when trying to read a file, even though the owner and group are set correctly, it is likely that you lack execute (x) permission for one of the directories in the path. In Linux, to access a file, you need to have x permission on all directories in the path to be able to "pass through" them.

28. In Linux, there are three main data streams for processes:

• stdin (standard input) — the stream from which the process reads data (usually the keyboard).
• stdout (standard output) — the stream to which the process outputs data (usually the screen).
• stderr (standard error stream) — the stream for outputting error messages.

These streams can be redirected to control input and output of programs.