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Why use double indirection? or Why use pointers to pointers?
...oring lol
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int wordsinsentence(char **x) {
int w = 0;
while (*x) {
w += 1;
x++;
}
return w;
}
int wordsinmono(char ***x) {
int w = 0;
while (*x) {
w += wordsinsentence(*x);
...
MySQL - length() vs char_length()
...
LENGTH() returns the length of the string measured in bytes.
CHAR_LENGTH() returns the length of the string measured in characters.
This is especially relevant for Unicode, in which most characters are encoded in two bytes. Or UTF-8, where the number of by...
Java executors: how to be notified, without blocking, when a task completes?
...blic class GetTaskNotificationWithoutBlocking {
public static void main(String... argv) throws Exception {
ExampleService svc = new ExampleService();
GetTaskNotificationWithoutBlocking listener = new GetTaskNotificationWithoutBlocking();
CompletableFuture<String> f = Completable...
Why are C character literals ints instead of chars?
...nerating code to get an 'A' into the register may prefer to waste a little extra memory and encode the value as 0 'A' or 'A' 0 - depending on endianness, and also ensuring it is aligned properly (i.e. not at an odd memory address).
My guess is that C's simply carried this level of CPU-centric behav...
Equals(=) vs. LIKE
... these operators!
= is a comparison operator that operates on numbers and strings. When comparing strings, the comparison operator compares whole strings.
LIKE is a string operator that compares character by character.
To complicate matters, both operators use a collation which can have important...
How do I execute a command and get the output of the command within C++ using POSIX?
...stream>
#include <memory>
#include <stdexcept>
#include <string>
#include <array>
std::string exec(const char* cmd) {
std::array<char, 128> buffer;
std::string result;
std::unique_ptr<FILE, decltype(&pclose)> pipe(popen(cmd, "r"), pclose);
...
Bitwise operation and usage
...hexadecimal colours.
For example, here's a Python function that accepts a String like #FF09BE and returns a tuple of its Red, Green and Blue values.
def hexToRgb(value):
# Convert string to hexadecimal number (base 16)
num = (int(value.lstrip("#"), 16))
# Shift 16 bits to the right, a...
How do I find where an exception was thrown in C++?
...#endif
#include <execinfo.h>
#include <signal.h>
#include <string.h>
#include <iostream>
#include <cstdlib>
#include <stdexcept>
void my_terminate(void);
namespace {
// invoke set_terminate as part of global constant initialization
static const bool SE...
Why is argc not a constant?
...ough getopt's prototype suggests it won't modify argv[] but may modify the strings pointed to, the Linux man page indicates that getopt permutes its arguments, and it appears they know they're being naughty. The man page at the Open Group does not mention this permutation.)
Putting const on argc a...
How does HTTP file upload work?
... here ...
------WebKitFormBoundaryePkpFF7tjBAqx29L--
NOTE: each boundary string must be prefixed with an extra --, just like in the end of the last boundary string. The example above already includes this, but it can be easy to miss. See comment by @Andreas below.
Instead of URL encoding the form...