safe way to apply patch

From: BL (c50342182003_at_gmail.com)
Date: 11/24/05


Date: 24 Nov 2005 07:23:14 -0800

Hi,
If I need to apply APAR into the AIX by use smitty update_all,
I choose "no commit" and "SAVE replaced file".
Is it the safest way to apply patch? Thanks