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Why don't structs support inheritance?
...Basically, they're supposed to hold simple data and therefore do not have "extra features" such as inheritance. It would probably be technically possible for them to support some limited kind of inheritance (not polymorphism, due to them being on the stack), but I believe it is also a design choice ...
What's the difference between a file descriptor and file pointer?
...LE Structure returned by fopen
typedef struct
{
unsigned char *_ptr;
int _cnt;
unsigned char *_base;
unsigned char *_bufendp;
short _flag;
short _file;
int __stdioid;
char *__newbase;
#ifdef _THREAD_SAFE
...
Are there any downsides to passing structs by value in C, rather than passing a pointer?
...e output parameters be listed first before input parameters, e.g. int func(char* out, char *in);
– zooropa
Apr 29 '09 at 12:29
...
Use '=' or LIKE to compare strings in SQL?
...he (almost religious) discussion, if you should use LIKE or '=' to compare strings in SQL statements.
9 Answers
...
install / uninstall APKs programmatically (PackageManager vs Intents)
...ion result notification.
Example code for invoking the uninstall dialog:
String app_pkg_name = "com.example.app";
int UNINSTALL_REQUEST_CODE = 1;
Intent intent = new Intent(Intent.ACTION_UNINSTALL_PACKAGE);
intent.setData(Uri.parse("package:" + app_pkg_name));
intent.putExtra(Intent.EXTRA_RET...
Compare DATETIME and DATE ignoring time portion
...ng, contrived example.
--112 is ISO format 'YYYYMMDD'
declare @filterDate char(8) = CONVERT(char(8), GETDATE(), 112)
select
*
from
Sales.Orders
where
CONVERT(char(8), OrderDate, 112) = @filterDate
In a perfect world, performing any manipulation to the filtered column should be avo...
Does delete on a pointer to a subclass call the base class destructor?
...n this will happen when the containing object is destroyed.
class A
{
char *someHeapMemory;
public:
A() : someHeapMemory(new char[1000]) {}
~A() { delete[] someHeapMemory; }
};
class B
{
A* APtr;
public:
B() : APtr(new A()) {}
~B() { delete APtr; }
};
class C
{
A Amemb...
How to use NULL or empty string in SQL
I would like to know how to use NULL and an empty string at the same time in a WHERE clause in SQL Server. I need to find records that have either null values or an empty string. Thanks.
...
Difference between a Structure and a Union
...re that value.
union foo {
int a; // can't use both a and b at once
char b;
} foo;
struct bar {
int a; // can use both a and b simultaneously
char b;
} bar;
union foo x;
x.a = 3; // OK
x.b = 'c'; // NO! this affects the value of x.a!
struct bar y;
y.a = 3; // OK
y.b = 'c'; // OK
ed...
Why does Git treat this text file as a binary file?
...ut need of a null (00h) byte for anything other than the nul char (the 'C' string terminator). Thus Git's text definition is that the content (well the first 1k bytes) should not have a null byte when utf-8 encoded. Try stackoverflow.com/questions/2241348/… for a fun read. My original comment ref...