std::strchr(3)

💖 std::strchr(3) — C++ Standard Library 💖

okay bestie, welcome to the <cstring> chapter of the group chat, the manual page is literally called std::strchr and yes it does exactly what the name screams. sit down, hydrate, let's go 🫶

✨ NAME ✨

std::strchr — it finds a character in a string. that's it. that's the whole vibe. 💅

🌸 Synopsis 🌸

first things first, this cutie lives in the header <cstring> — don't forget to include it or the compiler will simply not know her:

const char* strchr( const char* str, int ch );
    char* strchr(       char* str, int ch );

so here's the tea: strchr finds the first occurrence of the character static_cast<char>(ch) in the byte string pointed to by str. like, first match, no searching backwards, we move forward only. main character energy 🎀

and the iconic detail — the terminating null character is considered to be a part of the string and can be found if you're searching for '\0'. so yes, you can hunt down the null terminator on purpose. it's giving "the end is also a destination". lowkey obsessed 😭

🦋 Parameters 🦋

• str — pointer to the null-terminated byte string to be analyzed. they're the one getting searched, be nice to them.
• ch — character to search for. this is your target, your person, your 'T' if you will.

👑 Return value 👑

you get a pointer to the found character in str — iconic, precise, exactly where you wanted it. OR a null pointer if no such character is found, which is the polite way of saying "she's not here, bestie" 💀

🌈 Example 🌈

// Run this code — fr fr, this one is a classic:

#include <cstring>
#include <iostream>

int main()
{
    const char* str = "Try not. Do, or do not. There is no try.";
    char target = 'T';
    const char* result = str;

    while ((result = std::strchr(result, target)) != nullptr)
    {
        std::cout << "Found '" << target
                  << "' starting at '" << result << "'\n";

        // Increment result, otherwise we'll find target at the same location
        ++result;
    }
}

note the ++result — that's the whole trick. without it you'd find the same target at the same location forever and ever, an infinite loop, a cursed timeline 🙈 advance the pointer, keep it moving.

⭐ Output ⭐

Found 'T' starting at 'Try not. Do, or do not. There is no try.'
Found 'T' starting at 'There is no try.'

look at that. two hits. slay 🔥

💜 See also 💜

• memchr — searches an array for the first occurrence of a character (function)
• find — finds the first occurrence of the given substring (public member function of std::basic_string<CharT,Traits,Allocator>)
• wcschr — finds the first occurrence of a wide character in a wide string (function)
• strrchr — finds the last occurrence of a character (function)
• strpbrk — finds the first location of any character from a set of separators (function)
• C documentation for strchr — for when you want the origin story

okay that's the whole page, you're officially fluent 🧚 from http://cppreference.com, dated 2024.06.10, page std::strchr(3). go forth and find your characters, bestie 💖✨