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Is char signed or unsigned by default?
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The book is wrong. The standard does not specify if plain char is signed or unsigned.
In fact, the standard defines three distinct types: char, signed char, and unsigned char. If you #include <limits.h> and then look at CHAR_MIN, you can find...
Different floating point result with optimization enabled - compiler bug?
The below code works on Visual Studio 2008 with and without optimization. But it only works on g++ without optimization (O0).
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MySQL, better to insert NULL or empty string?
...a lot of different fields. Some of the fields are optional while some are mandatory. In my DB I have a table which holds all these values, is it better practice to insert a NULL value or an empty string into the DB columns where the user didn't put any data?
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How to solve PHP error 'Notice: Array to string conversion in…'
I have a PHP file that tries to echo a $_POST and I get an error, here is the code:
5 Answers
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cscope or ctags why choose one over the other? [closed]
I primarily use vim / gvim as an editor and am looking at using a combination of lxr (the Linux Cross Reference) and either cscope or ctags for exploring the kernel source. However, I haven't ever used either cscope or ctags and would like to hear why one might choose one over the other t...
Why is NaN not equal to NaN? [duplicate]
The relevant IEEE standard defines a numeric constant NaN (not a number) and prescribes that NaN should compare as not equal to itself. Why is that?
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Should we pass a shared_ptr by reference or by value?
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This question has been discussed and answered by Scott, Andrei and Herb during Ask Us Anything session at C++ and Beyond 2011. Watch from 4:34 on shared_ptr performance and correctness.
Shortly, there is no reason to pass by value, unless the goal is to sha...
What's the difference between “Solutions Architect” and “Applications Architect”? [closed]
... from application, to solution, to enterprise, at multiple companies large and small. I've come to the conclusion that the future in our technology industry is one mostly without architects. If this sounds crazy to you, wait a few years and your company will probably catch up, or your competitors wh...
Conventions for exceptions or error codes
...error codes.
The default behaviour of an exception is to unwind the stack and stop the program, if I'm writing a script an and I go for a key that's not in a dictionary it's probably an error, and I want the program to halt and let me know all about that.
If, however, I'm writing a piece of code ...
Lock, mutex, semaphore… what's the difference?
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A lock allows only one thread to enter the part that's locked and the lock is not shared with any other processes.
A mutex is the same as a lock but it can be system wide (shared by multiple processes).
A semaphore does the same as a mutex but allows x number of threads to enter, this...