RT-Thread/rt-thread: https://github.com/RT-Thread/rt-thread.git @ b24447a60a6941568d58dd1ca358951674924ed2

Meco Man 740a810274 [errno][libc] 解决sys头文件在libc未开启时的引入问题		4 lat temu
..
none-gcc	740a810274 [errno][libc] 解决sys头文件在libc未开启时的引入问题	4 lat temu
sys	1a55702ccb 修复DST_NONE 等宏定义位置放错导致报错的问题	4 lat temu
SConscript	740a810274 [errno][libc] 解决sys头文件在libc未开启时的引入问题	4 lat temu
dirent.h	f9ba41f4c2 更改libc目录为common 以及 none-gcc	4 lat temu
readme.md	f9ba41f4c2 更改libc目录为common 以及 none-gcc	4 lat temu
stdlib.c	3c05a4e719 [compoenets] auto & manual formatted	4 lat temu
termios.h	3c05a4e719 [compoenets] auto & manual formatted	4 lat temu
time.c	a5f7635f31 remove libc_errno.h & libc_limits.h	4 lat temu
unistd.c	19347ed454 [libc][unistd] 完善isatty()	4 lat temu

Attentions

This folder is "common" for all toolchains.
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'])
```