Syscalls naming convention

This is not an issue, it relates to coding conventions when it comes to OS dev, why do some syscalls like getcwd have "" (two underscores in the beginning of their names) unlike some other syscalls that do not? What is the significance of those underscores?

Also generally when should you use “__” in the beginning of naming certain labels in OS development?

found this

but it does not seem to hold up since some are named this way and some are not, and all of them are in the kernel space.

In the case of time() and __time(), the first is the stdlibc function signature. The second is os161’s internal name. The os161 internal version supports a resolution to ns while the stdlibc requires only the result in seconds.