So, I've a simple operating system and now want to

Question

So, I've a simple operating system and now want to

implement empty C systemcalls functions like for instance _open, _close, etc. So, now there are also reentrant versions and as far as I see newlib in my gnu toolchain always seem to call the reentrant version and thia one calls the non reentrant version. Is the reentrant version always implemented by standard C libraries? Can I somehow change the behavior so that a libc variant is used that does not include the reentrant versions? And is there a way to omit reentrant calls and dirsctly use the non reentrant versions? Are there any guidelines on this? The red hat newlib documentations just says that an OS should implement the systemcallsnd that there are also reentranr version, but it doesn't state whether the reentrant versions need to be implemented too, or how reentrant calls can be omitted?

I assume that in order to omit reentrant calls, one would need to rebuilt the libc without reentrant functions? And is there an old gnu toolchain version which has no reentrant calls implemented, and where I'd also need to provide reentrant calls? xD

0

24.05.2019