std::mbsinit(3)

💅 std::mbsinit 💅

okay so this is from the C++ Standard Libary, bestie, and the main character is std::mbsinit. no cap, it’s a tiny function with a very specific job. 🎀

🌸 NAME 🌸

std::mbsinit - std::mbsinit (yes, that’s the name twice — we love a self-titled icon 👑).

✨ Synopsis ✨

Defined in header <cwchar>.

int mbsinit( const std::mbstate_t* ps);

If ps is not a null pointer, the mbsinit function determines whether the pointed-to std::mbstate_t object describes the initial conversion state. that’s the vibe check, literally ✨

📝 Notes 📝

okay so here’s the tea: although a zero-initialized std::mbstate_t always represents the initial conversion state, there may be other values of std::mbstate_t that also represent the initial conversion state. so don’t assume zero is the only icon who can serve initial-conversion-state energy 💅

🎯 Parameters 🎯

• ps — pointer to the std::mbstate_t object to examine.

💖 Return value 💖

0 if ps is not a null pointer and does not represent the initial conversion state, nonzero value otherwise. periodt. 💖

🌈 Example 🌈

// Run this code

#include <clocale>
#include <cwchar>
#include <iostream>
#include <string>

int main()
{
    // allow mbrlen() to work with UTF-8 multibyte encoding
    std::setlocale(LC_ALL, "en_US.utf8");
    // UTF-8 narrow multibyte encoding
    std::string str = "水"; // or u8"\u6c34" or "\xe6\xb0\xb4"
    std::mbstate_t mb = std::mbstate_t();
    (void)std::mbrlen(&str[0], 1, &mb);
    if (!std::mbsinit(&mb))
        std::cout << "After processing the first 1 byte of " << str
                  << " the conversion state is not initial\n";

    (void)std::mbrlen(&str[1], str.size() - 1, &mb);
    if (std::mbsinit(&mb))
        std::cout << "After processing the remaining 2 bytes of " << str
                  << ", the conversion state is initial conversion state\n";
}

🖥️ Output 🖥️

After processing the first 1 byte of 水 the conversion state is not initial
After processing the remaining 2 bytes of 水, the conversion state is initial conversion state

👀 See also 👀

• mbstate_t (class) — conversion state information necessary to iterate multibyte character strings.
• C documentation for mbsinit.

okay that’s the whole page, bestie — source is http://cppreference.com, version/date is 2024.06.10, and the manual page is std::mbsinit(3). byeee 💖🫶🎀