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What is the difference between cout, cerr, clog of iostream header in c++? When to use which one?
... happen.
#include <iostream>
#include <fstream>
#include <string>
void f(std::ostream &os)
{
std::cin.clear(); // clear EOF flags
std::cin.seekg(0, std::cin.beg); // seek to begin
std::string line;
while(std::getline(std::cin, line)) //input from the file ...
How to disable GCC warnings for a few lines of code
...ing puts.c source code
#include <stdio.h>
int main(int argc, const char *argv[])
{
while (*++argv) puts(*argv);
return 0;
}
It will not compile because argc is unused, and the settings are hardcore (-W -Wall -pedantic -Werror).
There are 5 things you could do:
Improve the source...
How to comment out a block of Python code in Vim
...' at first column with ''. <cr>:noh<cr> just clears the search string so nothing is left highlighted when you are done.
– cdated
Sep 22 '16 at 16:06
1
...
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
...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...
Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() ...
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
...
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...
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...
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
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