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Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
to drawRect or not to drawRect (when should one use drawRect/Core Graphics vs subviews/images and wh
...bviews whenever you can. You can be more productive, and take advantage of all the OO mechanisms that should things easier to maintain. Use Core Graphics when you can't get the performance you need out of UIKit, or you know trying to hack together drawing effects in UIKit would be more complicated....
How do I find duplicates across multiple columns?
...simple and efficient means to locate unwanted repetition, whilst also list all affected rows and all wanted columns:
SELECT
t.*
FROM (
SELECT
s.*
, COUNT(*) OVER (PARTITION BY s.name, s.city) AS qty
FROM stuff s
) t
WHERE t.qty > 1
ORDER BY t.name, t.city
While most...
How should I print types like off_t and size_t?
...6, some_uint16_t);
They are listed in the manpage of inttypes.h.
Personally, I would just cast the values to unsigned long or long like another answer recommends. If you use C99, then you can (and should, of course) cast to unsigned long long or long long and use the %llu or %lld formats respect...
How do you read a file into a list in Python? [duplicate]
...each line might have. When the with ends, the file will be closed automatically for you. This is true even if an exception is raised inside of it.
2. use of list comprehension
This could be considered inefficient as the file descriptor might not be closed immediately. Could be a potential issue wh...
Specifically, what's dangerous about casting the result of malloc?
Now before people start marking this a dup, I've read all the following, none of which provide the answer I'm looking for:
...
UTF-8 byte[] to String
... You can see in here the java.nio.charset.Charset.availableCharsets() map all the charsets not just the charsets in the StandardCharsets. And if you want to use some other charset and still want to prevent the String constructor from throwing UnsupportedEncodingException you may use java.nio.charse...
Is there a difference between foo(void) and foo() in C++ or C?
...tion across both languages and make our headers multilingual (though we usually need to do some more things to the headers to make them truly cross-language; namely, wrap them in an extern "C" if we're compiling C++).
share
...
Practical use of `stackalloc` keyword
Has anyone ever actually used stackalloc while programming in C#? I am aware of what is does, but the only time it shows up in my code is by accident, because Intellisense suggests it when I start typing static , for example.
...
What are the git concepts of HEAD, master, origin?
...
I highly recommend the book "Pro Git" by Scott Chacon. Take time and really read it, while exploring an actual git repo as you do.
HEAD: the current commit your repo is on. Most of the time HEAD points to the latest commit in your current branch, but that doesn't have to be the case. HEAD rea...