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Python argparse mutual exclusive group
... answered Dec 28 '14 at 10:38
Oz123Oz123
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Is there a way for multiple processes to share a listening socket?
... normal stream socket that you can use to handle the client's request. The OS manages the queue of incoming connections behind the scenes.
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Best way to represent a fraction in Java?
...on("Unknown format '" + s + "'");
}
// this translates 23.123e5 to 25,123 / 1000 * 10^5 = 2,512,300 / 1 (GCD)
String whole = m.group(1);
String decimal = m.group(2);
String exponent = m.group(3);
String n = whole;
// 23.123 => 23123
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sed in-place flag that works both on Mac (BSD) and Linux
...backups that works both on Linux and Mac? While the BSD sed shipped with OS X seems to need sed -i '' … , the GNU sed Linux distributions usually come with interprets the quotes as empty input file name (instead of the backup extension), and needs sed -i … instead.
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What is the meaning and difference between subject, user and principal?
...clarify "User - subset of principal"? If John is the subject and "account #123" is his principal, the user is who? Are there two John's? Since Genus > Species > Individual is increasingly specific, John (user) should be more specific than John (subject). Or am I missing something?
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What's an easy way to read random line from a file in Unix command line?
... package that does exactly what you want, though not available in all distros. On its home page it actually recommends the use of shuf instead (which didn't exist when it was created, I believe). shuf is part of the GNU coreutils, rl is not.
rl -c 1 $FILE
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Insert a line at specific line number with sed or awk
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OS X / macOS / FreeBSD sed
The -i flag works differently on macOS sed than in GNU sed.
Here's the way to use it on macOS / OS X:
sed -i '' '8i\
8 This is Line 8' FILE
See man 1 sed for more info.
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How to stop app that node.js express 'npm start'
... provides for a stop script too:
npm help npm-scripts
prestop, stop, poststop: Run by the npm stop command.
Set one of the above in your package.json, and then use npm stop
npm help npm-stop
You can make this really simple if you set in app.js,
process.title = myApp;
And, then in scri...
How to fix a locale setting warning from Perl?
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Your OS doesn't know about en_US.UTF-8.
You didn't mention a specific platform, but I can reproduce your problem:
% uname -a
OSF1 hunter2 V5.1 2650 alpha
% perl -e exit
perl: warning: Setting locale failed.
perl: warning: Please...
How can I efficiently download a large file using Go?
...d via http (error checks omitted for brevity):
import ("net/http"; "io"; "os")
...
out, err := os.Create("output.txt")
defer out.Close()
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resp, err := http.Get("http://example.com/")
defer resp.Body.Close()
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n, err := io.Copy(out, resp.Body)
The http.Response's Body is a Reader, so you can ...