various types of arguments /dev/null

argument argument description
> /dev/null throw away stdout
1> /dev/null throw away stdout
2> /dev/null throw away stderr
&> /dev/null throw away both stdout and stderr

> is the operator used to redirect output. 2 is a reference to the standard error output stream, i.e. 2> = redirect error output.

/dev/null is the ‘null device’ which just swallows any input provided to it. You can combine the two to effectively throw away output from a command.

Usages /dev/null example

Suppress rm warnings

$ rm tempfl.txt 2> /dev/null

Redirect script output to /dev/null

$ ./myscript.sh 2> /dev/null

The latter has a drawback of missing all other warning messages produced by your script.

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