RT-Thread/rt-thread: https://github.com/RT-Thread/rt-thread.git @ 42a136288dc7dab4bba688f2ffccbc955090a6bb

Man, Jianting (Meco) 6ce4a87492 [fcntl] create new fcntl.h file for vs (#5860)		%!s(int64=3) %!d(string=hai) anos
..
fcntl	6ce4a87492 [fcntl] create new fcntl.h file for vs (#5860)	%!s(int64=3) %!d(string=hai) anos
sys	bda32cdedb [libc] fix that some function cannot be found in unistd.h	%!s(int64=3) %!d(string=hai) anos
SConscript	c318dfa964 improve libc time and MSVC simulator (#5775)	%!s(int64=3) %!d(string=hai) anos
readme.md	76cab376ad [libc] 调整文件结构	%!s(int64=4) %!d(string=hai) anos

Attentions

This folder is "common" for toolchains, which only support ISO C, as an extension part, such as Keil-MDK and IAR.