log_method_arguments failed

[SteinsGate9]

the script use "nm -C -D" to get arguments of module, and i tried that on libc.so and i get

00072720 T pthread_rwlockattr_getkind_np
000726d0 T pthread_rwlockattr_getpshared
00072690 T pthread_rwlockattr_init
00072740 T pthread_rwlockattr_setkind_np
000726f0 T pthread_rwlockattr_setpshared
00072800 T pthread_rwlock_destroy
00072770 T pthread_rwlock_init
00072820 T pthread_rwlock_rdlock
00072c10 T pthread_rwlock_timedrdlock
00073030 T pthread_rwlock_timedwrlock
00072c40 T pthread_rwlock_tryrdlock
00073060 T pthread_rwlock_trywrlock

there's no signature info... And i checked that ELF format do not store signature info. So it there another way of getting signature of method by Frida?
Many thanks.