kill9/rocks/computers/software/langs/c++.md

3.3 KiB

C++ has good stuff

As stated in the C++ harmful section C++ is a mostly bad programming language. But the great things about C++ are REALLY great and worth mentioning:

Concurrency

Threads API

Let's be honest, no matter how much you love C, you have to recognize that the pthreads API are garbage. But C++'s threads API is much better:

#include <iostream>
#include <thread>
#include <mutex>

int j = 10;

std::mutex j_lock;

int
counter_1()
{
    for(int i = 0; i <=10000; i++) {
        j_lock.lock(); /* critical section begins here */
        j++;
        j_lock.unlock(); /* critical sectrion ends here */
    }
    return 0;
}

int
counter_2()
{
    for(int i = 0; i <=10000; i++) {
        j_lock.lock(); /* critical section begins here */
        j--;
        j_lock.unlock(); /* critical section begins here */
    }
    return 0;
}

int
main(void)
{
    std::thread t1(counter_1); /* This starts the thread automatically */
    std::thread t2(counter_2);
    
    t1.join(); /* wait for the thing to finish */
    t2.join();
    
    std::cout << j << std::endl;
}

Async functions and stuff

As far as I know, C doesn't have this (well, it does but as state above you'll have to have a lot of patience to work with pthreads). but C++ does.

#include &lt;iostream&gt;
#include &lt;future&gt;
    
int
do_stuff()
{
    /* this function takes its time to be completed */
    return 0; /* Everything's alright */
}
int
main()
{
    std::future&lt;int&gt; future = std::async(do_stuff);
    std::cout << "do_stuff() is being executed in the background" << std::endl;
    std::cout << "The return value of do_stuff is: " << future.get() << std::endl;
    return 0;
}

C compatibility

Yes, you can be a C++ wizard and all you want, but saying "C++ has a good syntax" is like saying "I love my job" -- You're only saying that to convince yourself to get up from bed every morning. C++ is backwards compatible with C. Meaning that you can call C functions from C++. So you can do all your programming in C and only use the cool C++ features.

Things C doesn't have

You can write literally anything in C, but implementing a linked list gets boring at the third time you do it (altough you can use things like libulz) . So C++ has all the abstraction a normal human could want. Such as vectors (dynamics arrays, in C you would have to do really weird shit with realloc() or implementing a linked list), actual strings (C strings are very based, and a literal chad move though).

Creating libs is easy

Due to portability, there are things that C++ can't do by itself, such as creating UNIX sockets, which as far as i know, sockets in C++ must use the C sockets API. As stated before, calling C functions from C++ is very trivial, and you just have to call them. Converting C++ data types to C is trivial, because they're either the same datatype or there's a method for converting it to the C data type (c_str for the case of std::string, which will convert it to char * datatype). So you can easily create C++-styles functions from C functions.

Despite that, don't write complex libs in C++, as C users would want to use it as well, looking at you, qt.