Difference between __NR_gettid and SYS_gettid

Question

I was just looking at the way to get unique thread ID's in Linux. The way I found was to do as syscall with either of the two parameters as arguments: __NR_gettid OR SYS_gettid.

Can anybody explain how they both differ with respect to each other?

Answer 1

Nothing

in <bits/syscall.h> there is this:

#define SYS_gettid __NR_gettid