em{io} is a safe and fast high-level and low-level character input/output library for bare-metal and RTOS based embedded systems with a very small binary footprint.
// High-level
std::string str = emio::format("The answer is {}.", 42); // Format argument.
int answer{};
emio::result<void> scan_res = emio::scan(str, "The answer is {}.", answer); // Scan input string.
if (scan_res) {
emio::print("The answer is {}.", answer); // Output to console.
}
// Without using heap.
emio::static_buffer<128> buf{};
emio::format_to(buf, "The answer is {:#x}.", 42).value();
buf.view(); // <- The answer is 0x2a.
// Low-level
emio::writer wrt{buf};
wrt.write_str(" In decimal: ").value();
wrt.write_int(42).value();
wrt.write_char('.').value();
buf.view(); // <- The answer is 0x2a. In decimal: 42.
emio::reader rdr{"17c"};
EMIO_TRY(uint32_t number, rdr.parse_int<uint32_t>()); // <- 17
EMIO_TRY(char suffix, rdr.read_char()); // <- cThis library is in beta status! Please help to make it fly!
- API documentation
- Try emio online.
Yet another character input/output library
Bare-metal and RTOS based embedded systems do have special requirements which are mostly overlooked by the C++ standard, its implementations and other libraries.
Therefore, this library:
- has a very small binary footprint (~38 times smaller than fmtlib!)
- returns a result object instead of throwing an exception
- provides a high-level and low-level API which can be used at compile-time
Read more about it in the DESIGN document.
Including emio in your project
- With CMake and fetch content
FetchContent_Declare(
emio
GIT_TAG main
GIT_REPOSITORY https://github.com/Viatorus/emio.git
GIT_SHALLOW TRUE
)
FetchContent_MakeAvailable(emio)- Download the single header file generated with Quom
- From Conan Center
A compiler supporting C++20 is required. Tested with GCC 11/12/13 and Clang 16/17.
Contributing
See the CONTRIBUTING document.
Licensing
em{io} is distributed under the MIT license.