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How to get error message when ifstream open fails
... another system call triggers an error between the execution of the f.open and use of errno.
On system with POSIX standard:
errno is thread-local; setting it in one thread does not affect its
value in any other thread.
Edit (thanks to Arne Mertz and other people in the comments):
e.wha...
How does facebook, gmail send the real time notification?
...sleading -- last i heard, they developed HipHop for the express purpose of converting PHP to C++, as PHP wasn't performing well enough.
– cHao
Oct 16 '11 at 7:14
...
What does “default” mean after a class' function declaration?
...e that function automatically.
With the introduction of move constructors and move assignment operators, the rules for when automatic versions of constructors, destructors and assignment operators are generated has become quite complex. Using = default and = delete makes things easier as you don't ...
Best practice: AsyncTask during orientation change
...
Do NOT use android:configChanges to address this issue. This is very bad practice.
Do NOT use Activity#onRetainNonConfigurationInstance() either. This is less modular and not well-suited for Fragment-based applications.
You can read m...
Is there documentation for the Rails column types?
...s; use these for math that needs to be accurate
See this post for examples and an in-depth explanation on the differences between floats and decimals.
Boolean:
Use to store true/false attributes (i.e. things that only have two states, like on/off)
Binary:
Use to store images, movies, and other...
When should I use a table variable vs temporary table in sql server?
...re details in table variable. It says that temp tables are always on disk, and table variables are in memory, that is to say, the performance of table variable is better than temp table because table variable uses less IO operations than temp table.
...
Storing DateTime (UTC) vs. storing DateTimeOffset
...n record the location and timezone for that user.
Secondly if you want to convert for display, you need to have a table of all local time offset transitions for that timezone, simply knowing the current offset is not enough, because if you are showing a date/time from six months ago the offset will...
what's data-reactid attribute in html?
...loqi70ccu80.0' />
</span>
</div>
It needs to be able to convert that back into the data structure above. The way it does that is with the unique data-reactid attributes. This is called inflating the component tree.
You might also notice that if React renders at the client-side, i...
How to vertically center a container in Bootstrap?
...lt;p><strong>Redirect</strong><br>Visitors where they converts more.</p>
</li>
<li>
<span><i class="fa fa-cogs simple_bg top-features-bg"></i></span>
<p><strong>Track</strong...
Why must we define both == and != in C#?
..., you can compile this into a working library. This is legal code for F#, and only overloads the equality operator, not the inequality:
module Module1
type Foo() =
let mutable myInternalValue = 0
member this.Prop
with get () = myInternalValue
and set (value) = myInternalVa...