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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...
Is there a setting on Google Analytics to suppress use of cookies for users who have not yet given c
...et('clientId'));
});
ga('send', 'pageview');
Also check out this code at Convert Google Analytics cookies to Local/Session Storage
This script will not set any cookies, but still track via google analytics. This will actually have the same effect on privacy as using cookies, because google still ...
What is the proper way to URL encode Unicode characters?
...present characters from the unreserved set without translation, and should convert all other characters to bytes according to UTF-8, and then percent-encode those values. This requirement was introduced in January 2005 with the publication of RFC 3986. URI schemes introduced before this date are not...
Async image loading from url inside a UITableView cell - image changes to wrong image while scrollin
...ta = data
if error == nil {
// Convert the downloaded data in to a UIImage object
let image = UIImage(data: data!)
// Store the image in to our cache
self.previewImg[indexPath.row] = d...
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 ...
Change key pair for ec2 instance
... you will want to edit the authorized_keys file on the instance itself and convert to your new ssh public key.
The authorized_keys file is under the .ssh subdirectory under the home directory of the user you are logging in as. Depending on the AMI you are running, it might be in one of:
/home/ec2...
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.
...
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...