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What is this for 2>/dev/null in curl -s $proxyline $snortrules_url 2>/dev/null | tar xzOf - rules/*.rules rules/*.conf.... ?

Posted on 2004-04-29
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Last Modified: 2008-03-03
What is this for 2>/dev/null in curl -s $proxyline $snortrules_url 2>/dev/null | tar xzOf - rules/*.rules rules/*.conf.... ?
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Question by:acameron
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by:eeBlueShadow
ID: 10952052
When you run a command line program, by default all the output goes to screen. Output comes in 2 varieties - stdOut which is the 'normal' output and errOut which is the result of any error messages.

You can redirect either of those using the redirection operator >, so
progname > file.txt 2> otherfile.txt
will take the output from progname and put it into file.txt and any error messages will go into otherfile.txt

output redirected to /dev/null is just deleted.

_Blue
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by:acameron
ID: 10952399
So whats the 2 got to do with anything?
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eeBlueShadow earned 125 total points
ID: 10952775
> filename = standard output redirected to filename
2> otherfile = error messages redirected to otherfile

the 2 doesn't mean anything alone, it's part of the '2>' operator which refers to error output
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