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Please explain the exec() function and its family
What is the exec() function and its family? Why is this function used and how does its work?
7 Answers
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Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
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This approach will use the actual boolean type (and resolve to true and false) if the compiler supports it. (specifically, C++)
However, it would be better to check whether C++ is in use (via the __cplusplus macro) and actually use true and false.
In a C compiler, this i...
Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
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When and why are database joins expensive?
I'm doing some research into databases and I'm looking at some limitations of relational DBs.
7 Answers
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What are the differences between Perl, Python, AWK and sed? [closed]
just want to know what are the main differences among them? and the power of each language (where it's better to use it).
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When is JavaScript synchronous?
...ns). Is there a good reference anywhere about when it will be synchronous and when it will be asynchronous? Does jQuery affect this at all?
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Undefined behavior and sequence points
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C++98 and C++03
This answer is for the older versions of the C++ standard. The C++11 and C++14 versions of the standard do not formally contain 'sequence points'; operations are 'sequenced before' or 'unsequenced' or 'indetermina...
One Activity and all other Fragments [closed]
I am thinking of implementing one screen with Activity and all other sreens with Fragments and managing all the fragments thru the activity .
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Duplicate and rename Xcode project & associated folders [closed]
...d like to be able to duplicate an entire Xcode project, rename the project and the associated files without Xcode going mental, and without having to manually re-import all files to the project.
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Load and execution sequence of a web page?
...ve done some web based projects, but I don't think too much about the load and execution sequence of an ordinary web page. But now I need to know detail. It's hard to find answers from Google or SO, so I created this question.
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