Does stderr print to terminal?
The error message that is delivered via stderr is still sent to the terminal window. We can check the contents of the file to see whether the stdout output went to the file. The output from stdin was redirected to the file as expected. The > redirection symbol works with stdout by default.
Is stdout the terminal?
Stdout is not specified, so as outlined above, the terminal is the default value for stdout and the string “hello” is printed. The second version does the same, but points stdout to the file hello_file. txt.
What does printing to stderr do?
Stderr is the standard error message that is used to print the output on the screen or windows terminal. Stderr is used to print the error on the output screen or window terminal. Stderr is also one of the command output as stdout, which is logged anywhere by default.
How can you tell if output is stdout or stderr?
There’s no way to tell once the output has already been printed. In this case, both stdout and stderr are connected to the terminal, so the information about which stream was written to was already lost by the time the text appeared on your terminal; they were combined by the program before ever making it to the terminal.
How to tell if output of a command or shell script is stderr?
If you really want both stderr and stdout to be specific colours then you can do this: $ (echo “this is stdout”; echo “this is stderr” >&2) 2> > (GREP_COLORS=’ms=01;31′ grep .) 1> > (GREP_COLORS=’ms=01;32′ grep .) Usually STDERR will have the program name prepended to the message with a colon.
What to do if FD is open in stdout?
-t fd True if file descriptor fd is open and refers to a terminal. This detects if the output is coming from STDOUT. Returns nothing, since the output is being directed to cat. Thanks for contributing an answer to Unix & Linux Stack Exchange!
Why does stdin not return to the prompt?
On typing the command and hitting enter, you are not returned to your prompt since the console is expecting input to come from stdin; you type line after line of standard input followed by ^D.