What does “> /dev/null 2>&1″ mean? at Xaprb


From: What does “> /dev/null 2>&1″ mean? at Xaprb.

I remember being confused for a very long time about the trailing garbage in commands I saw in Unix systems, especially while watching compilers do their work. Nobody I asked could tell me what the funny greater-thans, ampersands and numbers after the commands meant, and search engines never turned up anything but examples of it being used without explanation. In this article I’ll explain those weird commands.

Here’s an example command:

Output redirection

The greater-thans (

) in commands like these redirect the program’s output somewhere. In this case, something is being redirected into

, and something is being redirected into


Standard in, out, and error

There are three standard sources of input and output for a program. Standard input usually comes from the keyboard if it’s an interactive program, or from another program if it’s processing the other program’s output. The program usually prints to standard output, and sometimes prints to standard error. These three file descriptors (you can think of them as “data pipes”) are often called STDIN, STDOUT, and STDERR.

Sometimes they’re not named, they’re numbered! The built-in numberings for them are 0, 1, and 2, in that order. By default, if you don’t name or number one explicitly, you’re talking about STDOUT.

Given that context, you can see the command above is redirecting standard output into

, which is a place you can dump anything you don’t want (often called the bit-bucket), then redirecting standard error into standard output (you have to put an

in front of the destination when you do this).

The short explanation, therefore, is “all output from this command should be shoved into a black hole.” That’s one good way to make a program be really quiet!

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7 Weirdest, Wackiest Products From CES 2010 – Tekzilla Daily Tip


Looking for the weirdest, wackiest products at CES 2010? We’ve got ‘em! Everything from the fasionable TV hat, to the eHealth USB cigarette. Oh, and there’s funny robots, the weirdest iPod holder ever, nano-toilets, the oddly named “Phubby” and a personal music system that gets a little too, well, personal. It’s all here in the wacky CES 2010 product roundup!

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This was written by a black gentleman in Texas and is so funny. What a great sense of humor and creativity!

When I was born, I was BLACK,

When I grew up, I was BLACK,

When I went in the sun, I stayed BLACK ,

When I got cold, I was BLACK,

When I was scared, I was BLACK,

When I was sick, I was BLACK,

And when I die, I’ll still be BLACK.

NOW, You ‘white’ folks . .

When you’re born, you’re PINK ,

When you grow-up, you’re WHITE,

When you go in the sun, you get RED ,

When you’re cold, you turn BLUE ,

When you’re scared, you’re YELLOW ,

When you get sick, you’re GREEN ,

When you bruise, you turn PURPLE ,

And when you die, you look GRAY .

So who y’all callin’

C O L O R ED folks?

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