apparently someone has been getting a head start on my dream life: Technology Enhanced Learning
and not only does she have a career that is so similar to my own passions and pursuits, but we share the same name!
so on top of that, I am ALSO an artist, an author of a ton of books, a Real Estate CFO, an election campaign donor to John Kerry & Barack Obama, an animal specialist, a graduate of a Milwaukee high school, working at a communications firm in London, a cinematographer, a countess from Swinton, a member of the Society of American Silversmiths, and a child caretaker.
Friday, August 22, 2008
Thursday, August 21, 2008
Sunday, August 17, 2008
Tuesday, August 5, 2008
Monday, August 4, 2008
Thursday, July 31, 2008
Unix 0, 1, and 2 Redirection
What does “> /dev/null 2>&1″ mean?
"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 [of them] explicitly, you’re talking about STDOUT. (emphasis added)
Given that context, you can see the command above is redirecting standard output into /dev/null, 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!"
"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 [of them] explicitly, you’re talking about STDOUT. (emphasis added)
Given that context, you can see the command above is redirecting standard output into /dev/null, 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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