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Why is the gets function so dangerous that it should not be used?
... you want to use fgets, which has the signature
char* fgets(char *string, int length, FILE * stream);
(fgets, if it reads an entire line, will leave the '\n' in the string; you'll have to deal with that.)
It remained an official part of the language up to the 1999 ISO C standard, but
it was offi...
Bidirectional 1 to 1 Dictionary in C#
...mber of pairs stored in the dictionary
/// </summary>
public Int32 Count
{
get { return firstToSecond.Count; }
}
/// <summary>
/// Removes all items from the dictionary.
/// </summary>
public void Clear()
{
firstToSecond.Clear();...
Django - limiting query results
...t work in django on a queryset: code.djangoproject.com/ticket/13089 If you convert the queryset to a list it will work.
– valem
Jan 9 at 16:48
1
...
Do you have to put Task.Run in a method to make it async?
...o the calling thread before it starts. In an async method, those "yield" points are await expressions.
This is very different than the term "asynchronous", as (mis)used by the MSDN documentation for years to mean "executes on a background thread".
To futher confuse the issue, async is very differe...
How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
... using performSelector:withObject:afterDelay: but with an argument like int / double / float ?
19 Answers
...
What exactly is a reentrant function?
...
{
foo(nullptr);
}
At first sight, everything seems ok… But wait:
int main()
{
foo(bar);
return 0;
}
If the lock on mutex is not recursive, then here's what will happen, in the main thread:
main will call foo.
foo will acquire the lock.
foo will call bar, which will call foo.
th...
Swift variable decorations with “?” (question mark) and “!” (exclamation mark)
...u don't check for nil you'll get a runtime error)
// Cannot be nil
var x: Int = 1
// The type here is not "Int", it's "Optional Int"
var y: Int? = 2
// The type here is "Implicitly Unwrapped Optional Int"
var z: Int! = 3
Usage:
// you can add x and z
x + z == 4
// ...but not x and y, because ...
Objective-C: Property / instance variable in category
...
.h-file
@interface NSObject (LaserUnicorn)
@property (nonatomic, strong) LaserUnicorn *laserUnicorn;
@end
.m-file
#import <objc/runtime.h>
static void * LaserUnicornPropertyKey = &LaserUnicornPropertyKey;
@implementat...
Constructors in Go
... have a struct like this :
type Thing struct {
Name string
Num int
}
then, if the zero values aren't fitting, you would typically construct an instance with a NewThing function returning a pointer :
func NewThing(someParameter string) *Thing {
p := new(Thing)
p.Name = somePara...
How do you create a Swift Date object?
... Time in Swift
In Swift, dates and times are stored in a 64-bit floating point number measuring the number of seconds since the reference date of January 1, 2001 at 00:00:00 UTC. This is expressed in the Date structure. The following would give you the current date and time:
let currentDateTime = Da...