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What does “dereferencing” a pointer mean?

...he pointer may be relative to some specific memory area, which the CPU may select based on CPU "segment" registers or some manner of segment id encoded in the bit-pattern, and/or looking in different places depending on the machine code instructions using the address. For example, an int* properly ...
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How to upload a file in Django? [closed]

...ss DocumentForm(forms.Form): docfile = forms.FileField( label='Select a file', help_text='max. 42 megabytes' ) 4. View: myproject/myapp/views.py A view where all the magic happens. Pay attention how request.FILES are handled. For me, it was really hard to spot the fact tha...
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What is the difference between user and kernel modes in operating systems?

...d 2 aren't used? How is the current ring determined? The current ring is selected by a combination of: global descriptor table: a in-memory table of GDT entries, and each entry has a field Privl which encodes the ring. The LGDT instruction sets the address to the current descriptor table. See ...
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How do you convert a byte array to a hexadecimal string, and vice versa?

... } return result; } static uint[] _Lookup32 = Enumerable.Range(0, 255).Select(i => { string s = i.ToString("X2"); return ((uint)s[0]) + ((uint)s[1] << 16); }).ToArray(); static string ByteArrayToHexViaLookupPerByte(byte[] bytes) { var result = new char[bytes.Length * 2]; ...
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Android Studio Project Structure (v.s. Eclipse Project Structure)

... For android Studio 3.0.1 and selected all features: Android O latest Android Auto Android things Android wear Android TV C++ support Kotlin support The structure in version 3.0.1 does not look at all like all other answers. Recent structure is as di...
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Wrap a delegate in an IEqualityComparer

... This is nice but if the key being selected was a value type there would be unnecessary boxing. Perhaps would be better to have a TKey for defining the key. – Graham Ambrose Aug 12 '11 at 13:19 ...
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What is polymorphism, what is it for, and how is it used?

...g different courses of action, you create interchangeable objects that you select based on your needs. That is the basic goal of polymorphism. share | improve this answer | ...
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Why can't I initialize non-const static member or static array in class?

...e symbol if it is used in the translation unit and ensures the linker only selects and leaves one copy if it's defined in multiple translation units due to it being in a comdat group. const at file scope makes the compiler never emit a symbol because it's always substituted immediately in the code u...
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How do I replace NA values with zeros in an R dataframe?

... mutate(myCol1 = if_else(is.na(myCol1), 0, myCol1)) Note: This works per selected column, if we need to do this for all column, see @reidjax's answer using mutate_each. share | improve this answer...
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ServiceStack vs ASP.Net Web API [closed]

...solveService<T>() method which returns an auto-wired instance of the selected service as seen in the Nortwind CustomerDetails Service example: var ordersService = base.ResolveService<OrdersService>(); var ordersResponse = (OrdersResponse)ordersService.Get( new Orders { CustomerId = ...