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Returning a C string from a function
...9+1 (=10!) bytes. This is important to know when you finally get around to allocating strings dynamically.
So, without this 'terminating zero', you don't have a string. You have an array of characters (also called a buffer) hanging around in memory.
Longevity of data:
The use of the function this...
How to use NSJSONSerialization
..."; // The Openweathermap JSON responder
NSURL *url = [[NSURL alloc]initWithString:urlString];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
NSURLResponse *response;
NSData *GETReply = [NSURLConnection sendSynchronousRequest:request returningResponse:&resp...
In C#, why is String a reference type that behaves like a value type?
...e (in all implementations of the CLR as of yet) stored on the stack. Stack allocating strings would break all sorts of things: the stack is only 1MB for 32-bit and 4MB for 64-bit, you'd have to box each string, incurring a copy penalty, you couldn't intern strings, and memory usage would balloon, et...
Running the new Intel emulator for Android
...developer It really works !!! When you installed HAXM how much RAM did you allocate ? I allocated 512 MB and its blazingly fast !
– GoodSp33d
May 3 '13 at 4:28
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What uses are there for “placement new”?
...
Placement new allows you to construct an object in memory that's already allocated.
You may want to do this for optimization when you need to construct multiple instances of an object, and it is faster not to re-allocate memory each time you need a new instance. Instead, it might be more efficien...
MySQL high CPU usage [closed]
...db_buffer_pool_size (if you're using innodb tables) as all of these memory allocations can have an affect on query performance which can cause MySQL to eat up CPU.
You'll also probably want to give the following a read over as they contain some good information.
How MySQL Uses Memory
MySQL System...
strdup() - what does it do in C?
...e as the following code:
char *strdup(const char *src) {
char *dst = malloc(strlen (src) + 1); // Space for length plus nul
if (dst == NULL) return NULL; // No memory
strcpy(dst, src); // Copy the characters
return dst; // Re...
What is the difference between class and instance methods?
...hen be used like so:
[MyClass aClassMethod];
MyClass *object = [[MyClass alloc] init];
[object anInstanceMethod];
Some real world examples of class methods are the convenience methods on many Foundation classes like NSString's +stringWithFormat: or NSArray's +arrayWithArray:. An instance method...
In Objective-C why should I check if self = [super init] is not nil?
...
For example:
[[NSData alloc] initWithContentsOfFile:@"this/path/doesn't/exist/"];
[[NSImage alloc] initWithContentsOfFile:@"unsupportedFormat.sjt"];
[NSImage imageNamed:@"AnImageThatIsntInTheImageCache"];
... and so on. (Note: NSData might throw...
String length in bytes in JavaScript
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If you only need the length, it might be overkill to allocate a new string, do the actual conversion, take the length, and then discard the string. See my answer above for a function that just computes the length in an efficient manner.
– lovasoa
...