How can I redirect all output to /dev/null?

bash pipe output-redirect dev-null
Benubird picture Benubird · Aug 2, 2013 · Viewed 61.3k times · Source

I want to run a program (google-chrome) in the background, but prevent it from outputting any messages to the terminal.

I tried doing this:

google-chrome 2>&1 1>/dev/null &

However, the terminal still fills up without messages like:

[5746:5746:0802/100534:ERROR:object_proxy.cc(532)] Failed to call method: org.chromium.Mtpd.EnumerateStorag...

What am I doing wrong? How do I redirect all the output to /dev/null?

Answer

Michael Martinez picture Michael Martinez · Aug 2, 2013

Redirection operators are evaluated left-to-right. You wrongly put 2>&1 first, which points 2 to the same place, as 1 currently is pointed to which is the local terminal screen, because you have not redirected 1 yet. You need to do either of the following:

2>/dev/null 1>/dev/null google-chrome &

Or

2>/dev/null 1>&2 google-chrome &

The placement of the redirect operators in relation to the command does not matter. You can put them before or after the command.

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