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Microsoft Windows is an operating system that features a graphical user interface and compatibility with a wide range of hardware and software, primarily for personal computers. UNIX is a multitasking, multi-user operating system developed for workstations, servers, and other devices

Echo is a Unix/Linux command tool used for displaying lines of text or string which are passed as arguments on the command line. This is one of the basic command in linux and most commonly used in shell scripts. In this tutorial, we will look at the different options of echo command.

Shell scripting is primarily used to automate repetitive system tasks, such as backing up files, monitoring system resources, and managing user accounts. By turning a series of commands into a script, system administrators can save time, increase accuracy, and simplify complex tasks.

Because of its open-source status, adaptability, control, and reliability, Linux is a preferred operating system among ethical hackers. For hacking and penetration testing, Linux provides a wide range of tools and applications. Its command-line interface makes difficult and automated tasks simpler.

I have a bash application that is producing some result, and I'd like to echo the result to either stdout or to a user chosen file. Because I also echo other interactive messages going to the screen, requiring the user to explicitly use the > redirection when he wants to echo the result to a file is not an option (*), as those messages would also appear in the file.

Right now I have a solution, but it's ugly.

if [ -z $outfile ]then    echo "$outbuf"    # Write output buffer to the screen (stdout)else    echo "$outbuf" > $outfile  # Write output buffer to filefi

I tried to have the variable $outfile to be equal to stdout, to &1 and perhaps something else but it would just write to file having that name and not actually to stdout. Is there a more elegant solution?

(*) I could cheat and use stderr for that purpose, but I think it's also quite ugly, isn't it?

The ps command writes the status of active processes and if the -m flag is given, displays the associated kernel threads to standard output. While the -m flag displays threads associated with processes using extra lines, you must use the -o flag with the THREAD field specifier to display extra thread-related columns.