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ping response “Request timed out.” vs “Destination Host unreachable”
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Destination Host Unreachable
This message indicates one of two problems: either the local system has no route to the desired destination, or a remote router reports that it has no route to the destination.
If the message is simply "Destination Host Unreachable," then there is...
Subtract two variables in Bash
...For simple integer arithmetic, you can also use the builtin let command.
ONE=1
TWO=2
let "THREE = $ONE + $TWO"
echo $THREE
3
For more info on let, look here.
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How to choose the right bean scope?
...on wide data/constants, such as dropdown lists which are the same for everyone, or managed beans without any instance variables and having only methods.
Abusing an @ApplicationScoped bean for session/view/request scoped data would make it to be shared among all users, so anyone else can see each oth...
Routing: The current request for action […] is ambiguous between the following action methods
...e [HttpGet].
Since both of your methods are GET, you should either rename one of the action methods or move it to a different controller.
Though your 2 Browse methods are valid C# overloads, the MVC action method selector can't figure out which method to invoke. It will try to match a route to the...
Difference between viewDidLoad and viewDidAppear
...ut while viewDidLoad is generally only called once and only once, there is one situation where it may be called again. Specifically, if you ever receive a didReceiveMemoryWarning, your non-visible views may be released (though the view controllers are untouched) and when you return back, viewDidLoad...
Do regular expressions from the re module support word boundaries (\b)?
...two'
>>> k = re.compile(r'\b%s\b' % word, re.I)
>>> x = 'one two three'
>>> y = k.search( x)
>>> y
<_sre.SRE_Match object at 0x100418850>
Also forgot to mention, you should be using raw strings in your code
>>> x = 'one two three'
>>> y ...
Real escape string and PDO [duplicate]
... process of migrating old code to use PDO and while the solution is a good one, people need to be aware of the fact that it will place quotes around the string. So if people are building out queries that already have quotes like "SELECT * FROM users WHERE username = '".$conn->quote($username)."'...
C# generic type constraint for everything nullable
... if (type.IsClass)
return;
throw new InvalidOperationException("Type is not nullable or reference type.");
}
public bool IsNull()
{
return item == null;
}
}
Then the following code compiles, but the last one (foo3) throws an exception in the constru...
What is an xs:NCName type and when should it be used?
I ran one of my xml files through a schema generator and everything generated was what was expected, with the exception of one node:
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Why are #ifndef and #define used in C++ header files?
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@CIsForCookies Punch "one definition rule" into your favorite search engine.
– David Schwartz
Jul 25 '19 at 1:57
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