snprintf()

template<typename... Args>

int fl::snprintf	(	char *	buffer,
		fl::size	size,
		const char *	format,
		const Args &...	args )

Snprintf-like formatting function that writes to a buffer.

Parameters

buffer	Output buffer to write formatted string to
size	Maximum number of characters to write (including null terminator)
format	Format string with placeholders like "%d", "%s", "%f" etc.
args	Arguments to format

Returns

Number of characters that would have been written if buffer was large enough

Supported format specifiers:

• d, i: integers (all integral types)
• u: unsigned integers
• o: octal integers
• f: floating point numbers
• s: strings (const char*, fl::string)
• c: characters
• x: hexadecimal (lowercase)
• X: hexadecimal (uppercase)
• p: pointers (formatted as 0x... hex)
• %%: literal % character

Example usage:

char buffer[100];
int len = fl::snprintf(buffer, sizeof(buffer), "Value: %d, Name: %s", 42, "test");

Definition at line 666 of file stdio.h.

                                                                                             {
    // Handle null buffer or zero size
    if (!buffer || size == 0) {
        return 0;
    }
    
    // Format to internal string stream
    sstream stream;
    printf_detail::format_impl(stream, format, args...);
    fl::string result = stream.str();
    
    // Get the formatted string length
    fl::size formatted_len = result.size();
    
    // Copy to buffer, ensuring null termination
    fl::size copy_len = (formatted_len < size - 1) ? formatted_len : size - 1;
    
    // Copy characters
    for (fl::size i = 0; i < copy_len; ++i) {
        buffer[i] = result[i];
    }
    
    // Null terminate
    buffer[copy_len] = '\0';
    
    // Return the number of characters actually written (excluding null terminator)
    // This respects the buffer size limit instead of returning the full formatted length
    return static_cast<int>(copy_len);
}

References args, FL_NOEXCEPT, format(), fl::printf_detail::format_impl(), and fl::sstream::str().

Referenced by fl::net::http::ChunkedWriter::chunkOverhead(), fl::audio::detector::Key::getKeyName(), getPort(), fl::net::http::HttpStreamTransport::idToString(), fl::third_party::TJpgInstanceDecoder::initializeDecoder(), fl::SerialPort::printf(), fl::third_party::TJpgInstanceDecoder::processChunk(), sprintf(), and fl::net::http::ChunkedWriter::writeChunk().

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