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What is the JavaScript equivalent of var_dump or print_r in PHP? [duplicate]
...ple 1: var_dump(1);
// returns 1: 'int(1)'
var output = '',
pad_char = ' ',
pad_val = 4,
lgth = 0,
i = 0;
var _getFuncName = function(fn) {
var name = (/\W*function\s+([\w\$]+)\s*\(/)
.exec(fn);
if (!name) {
return '(Anonymous)';
}
return name[1]...
How to convert std::string to LPCSTR?
...
str.c_str() gives you a const char *, which is an LPCSTR (Long Pointer to Constant STRing) -- means that it's a pointer to a 0 terminated string of characters. W means wide string (composed of wchar_t instead of char).
...
What are the advantages of using nullptr?
... be an advantage. But consider the following overloaded functions:
void f(char const *ptr);
void f(int v);
f(NULL); //which function will be called?
Which function will be called? Of course, the intention here is to call f(char const *), but in reality f(int) will be called! That is a big probl...
How to read a line from the console in C?
...ction to read your line. However, there seems to be no way to see how many characters it read. So you use fgetc:
char * getline(void) {
char * line = malloc(100), * linep = line;
size_t lenmax = 100, len = lenmax;
int c;
if(line == NULL)
return NULL;
for(;;) {
...
static constructors in C++? I need to initialize private static objects
... a class with a private static data member (a vector that contains all the characters a-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables are read...
How can I programmatically get the MAC address of an iphone
.....
- (NSString *)getMacAddress
{
int mgmtInfoBase[6];
char *msgBuffer = NULL;
size_t length;
unsigned char macAddress[6];
struct if_msghdr *interfaceMsgStruct;
struct sockaddr_dl *socketStruct;
NSString *errorFlag = NULL...
How to use shared memory with Linux in C
...mory.
#include <string.h>
#include <unistd.h>
int main() {
char parent_message[] = "hello"; // parent process will write this message
char child_message[] = "goodbye"; // child process will then write this one
void* shmem = create_shared_memory(128);
memcpy(shmem, parent_mes...
How to check if character is a letter in Javascript?
I am extracting a character in a Javascript string with:
14 Answers
14
...
__attribute__ - C/C++ - 清泛网 - 专注C/C++及内核技术
...数，其功能类似于printf：
//m=1；n=2
extern void myprint(const char *format,...) __attribute__((format(printf,1,2)));
//m=2；n=3
extern void myprint(int l，const char *format,...)
__attribute__((format(printf,2,3)));
需要特别注意的是，如果myprint是一个函数的成员...
My attempt at value initialization is interpreted as a function declaration, and why doesn't A a(())
...t of all, there is C. In C, A a() is function declaration. For example, putchar has the following declaration. Normally, such declarations are stored in header files, however nothing stops you from writing them manually, if you know how the declaration of function looks like. The argument names are ...