using > /dev/null when setting a variable

Question

So I found this answer and it didn't work for me. Couldn't find anything else.

Using >nul in a variable

What I'm trying to do is prevent output when setting a variable like this.

var=$(/bin/command.out)

If the command doesn't produce an error, then there's no problem. But if it does, it prints it all out to the terminal. I tried adding this, but it just seems to get ignored.

var=$(/bin/command.out) > /dev/null

I've treid putting everything to the right of the = in quotes. I've tried doing the escape character like that guy suggested. No luck.

Thanks.

just realized that link was for batch. I'm working in bash just so that's clear.

Answer 1

You need

var=$(/bin/command.out 2> /dev/null)

E.g.

$ var=$(not_a_command  2> /dev/null)
$ echo $var

$(uname  2> /dev/null)
$ echo $var
Linux

---

There are two outputs in Linux:

• 1> (commonly called STDOUT) which is the output
• 2> (called STDERR) which is the error output.

It was the error output which was writing the message.

You can find more details from the following chapter of the "Advanced Bash-Scripting Guide":
Chapter 20. I/O Redirection