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How to permanently add a private key with ssh-add on Ubuntu? [closed]
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This answer is so good that ssh-add shouldn't exist. Who wants to have a command that "temporarily" fixes a problem and breaks unexpectedly when you can just edit a config file permanently.
– RussellStewart
Aug 18 '14 at 18:55
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What's the use/meaning of the @ character in variable names in C#?
...u can't have a class with a member variable with the name "params". The proxy object that was generated contained a property that looked like this:
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Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
...e TRUE and FALSE according to its own rules, you're making their meanings explicit to programmers, and you're guaranteeing consistency within your program and any other library (assuming the other library follows C standards ... you'd be amazed).
Some History
Some BASICs defined FALSE as 0 and TR...
How to check if object (variable) is defined in R?
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You want exists():
R> exists("somethingUnknown")
[1] FALSE
R> somethingUnknown <- 42
R> exists("somethingUnknown")
[1] TRUE
R>
share
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Using group by on multiple columns
I understand the point of GROUP BY x .
2 Answers
2
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Executing multi-line statements in the one-line command-line?
I'm using Python with -c to execute a one-liner loop, i.e.:
17 Answers
17
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Is there a way to detect if a browser window is not currently active?
...ilitychange", onchange);
Current browser support:
Chrome 13+
Internet Explorer 10+
Firefox 10+
Opera 12.10+ [read notes]
The following code falls back to the less reliable blur/focus method in incompatible browsers:
(function() {
var hidden = "hidden";
// Standards:
if (hidden in docum...
Nokogiri installation fails -libxml2 is missing
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First, install the dependencies:
sudo apt-get install libxslt-dev libxml2-dev
If you still receive the error, you may be missing a compiler toolchain:
sudo apt-get install build-essential
You'll get the "libxml2 is missing" error if you're missing a build toolchain (at least I...
How to make the python interpreter correctly handle non-ASCII characters in string operations?
...ions:
The source file must be saved using the correct encoding in your text editor as well.
In Python 2, the unicode literal must have a u before it, as in s.replace(u"Â ", u"") But in Python 3, just use quotes. In Python 2, you can from __future__ import unicode_literals to obtain the Python 3 b...
Best way to give a variable a default value (simulate Perl ||, ||= )
...tly from the conditional operator, as it is specific to a null value. For example, if $_GET['name'] is set to an empty string, the first line would return an empty string, but we could return "john doe" by using $_GET['name'] ? $_GET['name'] : 'john doe'.
– VPhantom
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