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What does @synchronized() do as a singleton method in objective C?
...ES NOT do the same as @syncrhonized, it can be a substitute ONLY under the allocation of a singleton.
– jugutier
Aug 22 '16 at 21:32
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C++: What is the size of an object of an empty class?
...
@krish_oza: you think wrong. When you allocate a variable on stack, it cannot occupy zero bytes (because different variables need different addresses), hence the size 1 minimum. After that, it is up to the compiler. Similarly with new; when the space is allocat...
How do I profile memory usage in Python?
...
Python 3.4 includes a new module: tracemalloc. It provides detailed statistics about which code is allocating the most memory. Here's an example that displays the top three lines allocating memory.
from collections import Counter
import linecache
import os
import ...
How can I programmatically get the MAC address of an iphone
...
errorFlag = @"sysctl mgmtInfoBase failure";
else
{
// Alloc memory based on above call
if ((msgBuffer = malloc(length)) == NULL)
errorFlag = @"buffer allocation failure";
else
{
// Get system information, store in buffer
if (sysctl(mgmtI...
Cocoa Core Data efficient way to count entities
...ng NSManagedObjectContext *moc
NSFetchRequest *request = [[NSFetchRequest alloc] init];
[request setEntity:[NSEntityDescription entityForName:entityName inManagedObjectContext:moc]];
[request setIncludesSubentities:NO]; //Omit subentities. Default is YES (i.e. include subentities)
NSError *err;
N...
How to handle Objective-C protocols that contain properties?
... char * argv[])
{
@autoreleasepool {
Person *duncan=[[Person alloc]initConforming];
duncan.firstname=@"Duncan";
duncan.lastname=@"Smith";
[Viewer printLargeDescription:duncan];
Serial *x890tyu=[[Serial alloc]initConforming];
x890tyu.amount=1564...
How do I get the current username in Windows PowerShell?
... -- @Eoin
whoami -- @galaktor
If you want to access the Windows access token:
(more dependable option)
[System.Security.Principal.WindowsIdentity]::GetCurrent().Name -- @MarkSeemann
If you want the name of the logged in user
(rather than the name of the user running the PowerShell instan...
What does “Memory allocated at compile time” really mean?
... languages like C and C++, people often refer to static and dynamic memory allocation. I understand the concept but the phrase "All memory was allocated (reserved) during compile time" always confuses me.
...
Hidden Features of MySQL
...le resource when setting these parameters. For example sort_buffer_size is allocated only if MySQL needs to do a sort. Note: be careful not to run out of memory.
If you have many connects established (i.e. a web site without persistent connections) you might improve performance by setting thread_ca...
Custom HTTP headers : naming conventions
...d:
message-header = field-name ":" [ field-value ]
field-name = token
field-value = *( field-content | LWS )
field-content = <the OCTETs making up the field-value
and consisting of either *TEXT or combinations
of token, separators, and ...