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Why does InetAddress.isReachable return false, when I can ping the IP address?
...achine
// openPort = 22 - ssh, 80 or 443 - webserver, 25 - mailserver etc.
try {
try (Socket soc = new Socket()) {
soc.connect(new InetSocketAddress(addr, openPort), timeOutMillis);
}
return true;
} catch (IOException ex) {
return false;
}...
Defining a variable with or without export
... process. You would use this for (say) loop variables, temporary variables etc.
It's important to note that exporting a variable doesn't make it available to parent processes. That is, specifying and exporting a variable in a spawned process doesn't make it available in the process that launched it...
Understanding the main method of python [duplicate]
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Python does not have a defined entry point like Java, C, C++, etc. Rather it simply executes a source file line-by-line. The if statement allows you to create a main function which will be executed if your file is loaded as the "Main" module rather than as a library in another module.
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What is more efficient: Dictionary TryGetValue or ContainsKey+Item?
...ng out that the actual source is available now. none of the other answers/etc had a link to the actual source :D
– John Gardner
Jun 3 '16 at 17:32
1
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What are the benefits of functional programming? [closed]
...s its intent clearly, without being mixed up with control flow statements, etc. Because of the principles like side-effect free programming, it is much easier to reason about code, and check its correctness.
share
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Find and restore a deleted file in a Git repository
...he specified commit, so ~1 is the commit before, ~2 is two commits before, etc
– Nils Luxton
Sep 10 '12 at 15:07
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How to split a string in Java
...h needs regular expression construction and matching. Extra array created, etc.
– David
Jan 17 '19 at 23:38
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JavaScript hard refresh of current page
... the page AND refresh all the external resources (images, JavaScript, CSS, etc.).
2 Answers
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How to round a number to significant figures in Python
... . Doesn't protected against undefined like math.inf, or garbage like None etc
– AJP
Nov 28 '19 at 8:52
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Meaning of “[: too many arguments” error from if [] (square brackets)
...owever, and so may not be compatible with default shells called by /bin/sh etc.
This means on some systems, it might work from the console but not when called elsewhere, like from cron, depending on how everything is configured.
It would look like this:
VARIABLE=$(/some/command);
if [[ $VARIABL...