RT-Thread/rt-thread: https://github.com/RT-Thread/rt-thread.git @ 8ea33c2101cdc8d8d8a5f94479acca310fbbfb75

Meco Man 263d856fa4 update		5 lat temu
..
sys	6c7dd30532 add function settimeofday & stime	5 lat temu
SConscript	e927a53b41 精简exit abort system函数	5 lat temu
readme.md	d5f8830177 add newlib/dlib readme	5 lat temu
stdlib.c	263d856fa4 update	5 lat temu
termios.h	54143409ca 增加#include <rtconfig.h> 防止开启termios功能后报错	5 lat temu
time.c	ce4fabe158 add errno	5 lat temu
unistd.c	96acad78ba 将posix_getline.h termios.h 头文件包含从<>改为""以防止路径出现分歧	5 lat temu

Attentions

This folder is "common" for armlibc newlibc and dlib. It's not "common" for minilibc.
If you want to add new .c files, please do not forget to fix SConscript file too. eg:
```
if GetDepend('RT_USING_POSIX') == False:
    SrcRemove(src, ['unistd.c'])
```