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How much is the overhead of smart pointers compared to normal pointers in C++?
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shared_ptr has a significant overhead for creation because of it's memory allocation for the control block (which keeps the ref counter and a pointer list to all weak references). It has also a huge memory overhead because of this and the fact that std::shared_ptr is always a 2 pointer tuple (one t...
How to delete all Annotations on a MKMapView
...tion = [mapView userLocation];
NSMutableArray *pins = [[NSMutableArray alloc] initWithArray:[mapView annotations]];
if ( userLocation != nil ) {
[pins removeObject:userLocation]; // avoid removing user location off the map
}
[mapView removeAnnotations:pins];
[pins releas...
How do I add 1 day to an NSDate?
...te)")
Objective C :
NSDateComponents *dayComponent = [[NSDateComponents alloc] init];
dayComponent.day = 1;
NSCalendar *theCalendar = [NSCalendar currentCalendar];
NSDate *nextDate = [theCalendar dateByAddingComponents:dayComponent toDate:[NSDate date] options:0];
NSLog(@"nextDate: %@ ...", nex...
error_log per Virtual Host?
On one Linux Server running Apache and PHP 5, we have multiple Virtual Hosts with separate log files. We cannot seem to separate the php error_log between virtual hosts.
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HTML code for an apostrophe
..., it seems that some people don't like it for not being curly enough (as a token of typographic seriousness, I dunno...) but that's beside the point.
– Nicolas Le Thierry d'Ennequin
Nov 24 '14 at 9:41
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Sleeping in a batch file
...e:
DELAY.BAT:
@ECHO OFF
REM DELAY seconds
REM GET ENDING SECOND
FOR /F "TOKENS=1-3 DELIMS=:." %%A IN ("%TIME%") DO SET /A H=%%A, M=1%%B%%100, S=1%%C%%100, ENDING=(H*60+M)*60+S+%1
REM WAIT FOR SUCH A SECOND
:WAIT
FOR /F "TOKENS=1-3 DELIMS=:." %%A IN ("%TIME%") DO SET /A H=%%A, M=1%%B%%100, S=1%%C...
Submit form using a button outside the tag
...attribute. Basically
<form id="myform" method="get" action="something.php">
<input type="text" name="name" />
</form>
<input type="submit" form="myform" />
share
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im...
php execute a background process
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Write the process as a server-side script in whatever language (php/bash/perl/etc) is handy and then call it from the process control functions in your php script.
The function probably detects if standard io is used as the output stream and if it is then that will set the return value.....
How to add default value for html ? [closed]
...me="msg" placeholder="Your message here." onfocus='this.select()'>
<?php if (isset($_POST['encode'])) { echo htmlspecialchars($_POST['msg']);} ?>
</textarea>
In this case, $_POST['encode'] came from this:
<input class="input_bottom btn btn-default" type="submit" name="encode" va...
What is &&& operation in C
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There is no &&& operator or token in C. But the && (logical "and") and & (unary address-of or bitwise "and") operators do exist.
By the maximal munch rule, this:
c = i &&& i;
is equivalent to this:
c = i && & i;...