missing snippets in backups

Snippets are mostly used by more than one container, so the assumption is that they do not "belong" to a specific container.
 
Snippets are mostly used by more than one container, so the assumption is that they do not "belong" to a specific container.
Is there up to date info on snippets and hook scripts located?
Have tried using this resource, but arguments passed aren't matching...
https://github.com/proxmox/pve-manager/blob/master/vzdump-hook-script.pl
Would be nice to have a detailed and thorough reference so snippets and hook scripts could be utilized in an efficient manner instead of by trial and error.
 
there is a hook script for vzdump (the one you linked), and one for various guest hook points (/usr/share/pve-docs/examples/guest-example-hookscript.pl.)