2>/dev/null

> file redirects stdout to file
1> file redirects stdout to file
2> file redirects stderr to file
&> file redirects stdout and stderr to file

You can redirect stdout to stderr by doing 1>&2

echo test 1>&2 

1 is stdout. 2 is stderr.

Here is one way to remember this construct (altough it is not entirely accurate): at first, 2>1 may look like a good way to redirect stderr to stdout. However, it will actually be interpreted as “redirect stderr to a file named 1“. & indicates that what follows is a file descriptor and not a filename. So the construct becomes: 2>&1.

 
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