RT-Thread-Studio/sdk-rt-thread-source-code: https://github.com/RT-Thread-Studio/sdk-rt-thread-source-code.git @ v4.0.3

yaxing.chen c0257098b9 release rt-thread v4.0.3		4 éve
..
sys	c0257098b9 release rt-thread v4.0.3	4 éve
SConscript	c0257098b9 release rt-thread v4.0.3	4 éve
readme.md	c0257098b9 release rt-thread v4.0.3	4 éve
termios.h	c0257098b9 release rt-thread v4.0.3	4 éve
time.c	c0257098b9 release rt-thread v4.0.3	4 éve
unistd.c	c0257098b9 release rt-thread v4.0.3	4 éve

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'])
```