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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 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(;;) {
...
How to check if character is a letter in Javascript?
I am extracting a character in a Javascript string with:
14 Answers
14
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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...
hash function for string
... had nice results with djb2 by Dan Bernstein.
unsigned long
hash(unsigned char *str)
{
unsigned long hash = 5381;
int c;
while (c = *str++)
hash = ((hash << 5) + hash) + c; /* hash * 33 + c */
return hash;
}
...
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 ...
MD5 algorithm in Objective-C
...cess
@implementation NSString (MyAdditions)
- (NSString *)md5
{
const char *cStr = [self UTF8String];
unsigned char result[CC_MD5_DIGEST_LENGTH];
CC_MD5( cStr, (int)strlen(cStr), result ); // This is the md5 call
return [NSString stringWithFormat:
@"%02x%02x%02x%02x%02x%02x%...
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...
snprintf and Visual Studio 2010
...
Long version:
Here is the expected behavior for snprintf:
int snprintf( char* buffer, std::size_t buf_size, const char* format, ... );
Writes at most buf_size - 1 characters to a buffer. The resulting
character string will be terminated with a null character, unless
buf_size is zero. If ...
C++ Convert string (or char*) to wstring (or wchar_t*)
...nclude <string>
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
std::string narrow = converter.to_bytes(wide_utf16_source_string);
std::wstring wide = converter.from_bytes(narrow_utf8_source_string);
Longer online compilable and runnable example:
(They all sho...
