Function sys_fchmodat

freebsd/kern/vfs_syscalls.c:2839–2848

}
#endif
int
sys_fchmodat(struct thread *td, struct fchmodat_args *uap)
{

	if ((uap->flag & ~(AT_SYMLINK_NOFOLLOW | AT_RESOLVE_BENEATH)) != 0)
		return (EINVAL);

	return (kern_fchmodat(td, uap->fd, uap->path, UIO_USERSPACE,
	    uap->mode, uap->flag));
}

/*
 * Change mode of a file given path name (don't follow links.)