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Is non-blocking I/O really faster than multi-threaded blocking I/O? How?
...antage of nonblocking or asynchronous I/O is that your thread can continue its work in parallel. Of course you can achieve this also using an additional thread. As you stated for best overall (system) performance I guess it would be better to use asynchronous I/O and not multiple threads (so reducin...
Performance difference for control structures 'for' and 'foreach' in C#
... code snippet will give better performance? The below code segments were written in C#.
9 Answers
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What exactly do “u” and “r” string flags do, and what are raw string literals?
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There's not really any "raw string"; there are raw string literals, which are exactly the string literals marked by an 'r' before the opening quote.
A "raw string literal" is a slightly different syntax for a string literal, in which a backslash, \, is taken as meaning "just a backs...
Can I find out the return value before returning while debugging in Visual Studio?
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Not that I know of. Note that if you do add a variable, it will get removed by the compiler in release builds anyway...
Update:
This functionality has been added to VS2013.
You can see the return values in the autos windows or use $ReturnValue in the watch/immediate window.
The ...
Can you Run Xcode in Linux?
Can you run Xcode in Linux? Mac OS X was based on BSD Unix, so is it possible?
13 Answers
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Hibernate, @SequenceGenerator and allocationSize
... know the default behaviour of Hibernate when using @SequenceGenerator - it increases real database sequence by one , multiple this value by 50 (default allocationSize value) - and then uses this value as entity ID.
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Why does string::compare return an int?
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First, the specification is that it will return a value less
than, equal to or greater than 0, not necessarily -1 or 1.
Secondly, return values are rvalues, subject to integral
promotion, so there's no point in returning anything smaller.
In C++ (as in C),...
Ubuntu rails install fails on zlib
I've just moved over to Ubuntu 8.10 as my dev box; it's my first serious foray into Linux as a daily-use OS, and I'm having a hard time getting Rails going. I have followed a number of tutorials which all seem to work fine, but when I try and use gem install or gem update on anything, I get an erro...
MySQL: multiple tables or one table with many columns?
...time information is one-to-one (each user has one name and password), then it's probably better to have it one table, since it reduces the number of joins the database will need to do to retrieve results. I think some databases have a limit on the number of columns per table, but I wouldn't worry ab...
what is reverse() in Django
...ead django code sometimes, I see in some templates reverse() . I am not quite sure what this is but it is used together with HttpResponseRedirect. How and when is this reverse() supposed to be used?
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