/* Copyright 2011 Jun Wako This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ #ifndef SENDCHAR_H #define SENDCHAR_H #include #ifdef __cplusplus extern "C" { #endif /* transmit a character. return 0 on success, -1 on error. */ int8_t sendchar(uint8_t c); #ifdef __cplusplus } #endif #endif ubmit();'> [no description]
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# A printf / sprintf Implementation for Embedded Systems

[![Build Status](https://travis-ci.org/mpaland/printf.svg?branch=master)](https://travis-ci.org/mpaland/printf)
[![codecov](https://codecov.io/gh/mpaland/printf/branch/master/graph/badge.svg)](https://codecov.io/gh/mpaland/printf)
[![Coverity Status](https://img.shields.io/coverity/scan/14180.svg)](https://scan.coverity.com/projects/mpaland-printf)
[![Github Issues](https://img.shields.io/github/issues/mpaland/printf.svg)](http://github.com/mpaland/printf/issues)
[![Github Releases](https://img.shields.io/github/release/mpaland/printf.svg)](https://github.com/mpaland/printf/releases)
[![GitHub license](https://img.shields.io/badge/license-MIT-blue.svg)](https://raw.githubusercontent.com/mpaland/avl_array/master/LICENSE)

This is a tiny but **fully loaded** printf, sprintf and (v)snprintf implementation.
Primarily designed for usage in embedded systems, where printf is not available due to memory issues or in avoidance of linking against libc.
Using the standard libc printf may pull **a lot** of unwanted library stuff and can bloat code size about 20k or is not 100% thread safe. In this cases the following implementation can be used.
Absolutely **NO dependencies** are required, *printf.c* brings all necessary routines, even its own fast `ftoa` (float), `ntoa` (decimal) conversion.

If memory footprint is really a critical issue, floating point and 'long long' support and can be turned off via the `PRINTF_DISABLE_SUPPORT_FLOAT` and `PRINTF_DISABLE_SUPPORT_LONG_LONG` compiler switches.
When using printf (instead of sprintf/snprintf) you have to provide your own `_putchar()` low level function as console/serial output.


## Highlights and Design Goals

There is a boatload of so called 'tiny' printf implementations around. So why this one?
I've tested many implementations, but most of them have very limited flag/specifier support, a lot of other dependencies or are just not standard compliant and failing most of the test suite.
Therefore I decided to write an own, final implementation which meets the following items:

 - Very small implementation (around 600 code lines)
 - NO dependencies, no libs, just one module file
 - Support of all important flags, width and precision sub-specifiers (see below)
 - Support of decimal/floating number representation (with an own fast itoa/ftoa)