On a 16.04 instance, I got the list of system calls using man syscalls.
Most system calls have their own man page but a few do not:
$ man fremovexattr
No manual entry for fremovexattr
Ubuntu's website does have a manpage for that system call: http://manpages.ubuntu.com/manpages/wily/man2/lremovexattr.2.html
My question is what could possibly be the reason for not including the man pages for certain system calls?