Standard output, sometimes abbreviated stdout, refers to the standardized streams of data that are produced by command line programs (i.e., all-text mode programs) in Linux and other Unix-like operating systems. … Because the standard streams are plain text, they are by definition human readable.
What is stdout?
Stdout, also known as standard output, is the default file descriptor where a process can write output. In Unix-like operating systems, such as Linux, macOS X, and BSD, stdout is defined by the POSIX standard. Its default file descriptor number is 1. In the terminal, standard output defaults to the user’s screen.
Where does stdout go in Linux?
Standard output, as created at process creating time, goes to the console, your terminal or an X terminal. Exactly where output is sent clearly depends on where the process originated. would [con]catenate the file, by default, to our standard output i.e. our console or terminal screen.
What is stdout in terminal?
Stdout and stderr point to your terminal output (or the terminal process that ran the program) and are written to by the running program. What you type in is sent to and interpreted by the running program, and what the program wants to communicate to you is displayed in your terminal screen.
What is the use of stdout?
A built-in file object that is analogous to the interpreter’s standard output stream in Python. stdout is used to display output directly to the screen console. Output can be of any form, it can be output from a print statement, an expression statement, and even a prompt direct for input.
Does printf write to stdout?
Any call to printf will print to stdout, while calls to fprint while print to the specified stream. In the example you give, the second function call will print to stderr. Since you are printing an empty string, you won’t be doing much of anything on either stream, so you won’t see anything of note happen.
Is stdout saved?
stdout is just a file handle that by default is connected to the console, but could be redirected.
How do I find stderr in Linux?
Normally, STDOUT and STDERR are both output to your terminal. But it’s possible to redirect either and both. For example, the data sent to STDERR by a CGI script usually ends up in log file specified in the web server’s configuration. It’s possible for a program to get information about STDERR on a linux system.
What is systemd cat?
Description. systemd-cat may be used to connect the standard input and output of a process to the journal, or as a filter tool in a shell pipeline to pass the output the previous pipeline element generates to the journal.
What is the output of who command?
Explanation: who command output the details of the users who are currently logged in to the system. The output includes username, terminal name (on which they are logged in), date and time of their login etc. 11.