大约有 45,000 项符合查询结果（耗时：0.0432秒） [XML]
What is RSS and VSZ in Linux memory management
...-in-c/7212248#7212248 */
void ProcStat_init(ProcStatm *result) {
const char* statm_path = "/proc/self/statm";
FILE *f = fopen(statm_path, "r");
if(!f) {
perror(statm_path);
abort();
}
if(7 != fscanf(
f,
"%lu %lu %lu %lu %lu %lu %lu",
&(...
What is move semantics?
...:
#include <cstring>
#include <algorithm>
class string
{
char* data;
public:
string(const char* p)
{
size_t size = std::strlen(p) + 1;
data = new char[size];
std::memcpy(data, p, size);
}
Since we chose to manage the memory ourselves, we need...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
....h>
#include <stddef.h>
int main(void)
{
struct foo {
char c;
int x;
} __attribute__((packed));
struct foo arr[2] = { { 'a', 10 }, {'b', 20 } };
int *p0 = &arr[0].x;
int *p1 = &arr[1].x;
printf("sizeof(struct foo) = %d\n", (int)sizeof(str...
How do I trim whitespace from a string?
... Hello ")
' Hello'
Also, note that str.strip() removes other whitespace characters as well (e.g. tabs and newlines). To remove only spaces, you can specify the character to remove as an argument to strip, i.e.:
>>> " Hello\n".strip(" ")
'Hello\n'
...
How to add a line break in C# .NET documentation
...p;#160;</para>, <para>&nbsp;</para> or the invisible character...
– Dinei
Oct 23 '14 at 14:30
Th...
How can I add reflection to a C++ application?
...ld itself). This macro will be called like this:
REFLECTABLE
(
(const char *) name,
(int) age
)
So using Boost.PP we iterate over each argument and generate the data like this:
// A helper metafunction for adding const to a type
template<class M, class T>
struct make_const
{
ty...
What does template mean?
...er parameter:
template<unsigned int S>
struct Vector {
unsigned char bytes[S];
};
// pass 3 as argument.
Vector<3> test;
Template pointer parameter (passing a pointer to a function)
template<void (*F)()>
struct FunctionWrapper {
static void call_it() { F(); }
};
// pa...
Multiline strings in JSON
...for escaping the backslash, otherwise python will treat \n as
the control character "new line"
share
|
improve this answer
|
follow
|
...
Why is “while ( !feof (file) )” always wrong?
...e is again std::cin, just as before.
POSIX, write(2) to flush a buffer:
char const * p = buf;
ssize_t n = bufsize;
for (ssize_t k = bufsize; (k = write(fd, p, n)) > 0; p += k, n -= k) {}
if (n != 0) { /* error, failed to write complete buffer */ }
The result we use here is k, the numb...
Why historically do people use 255 not 256 for database field magnitudes?
You often see database fields set to have a magnitude of 255 characters, what is the traditional / historic reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me.
...