scoped_user_read_access_size
scoped_user_read_access_size(src, len, efault)
scoped_user_read_access_size(addr, nb, efault) {
scoped_user_read_access_size(ubuf, count, efault) {
scoped_user_read_access_size(uea, nb, efault)
scoped_user_read_access_size(uea, nb, efault)
scoped_user_read_access_size(usrc, sizeof(*(usrc)), elbl)