sorry... perhaps i was unclear.

I want to backup one directory to another on the same drive. I don't want to use mount at all. The script that i am adapting uses mount in the section that i made in blue in the original post. The function of that section was to ensure that the device being used to backup to (in the script that i am adapting from) was mounted Read Write, and then at the end they unmount Read Only. I didn't describe this very well in my previous post.

But i am not trying to backup to an external device. Instead, i am simply backing up to another directory on the same file system (i am aware of the risks involved with this, it is on a Raid array using raid 5). The file system that i am backing up is huge and making it inaccessible to other users while the backup takes place is not really an option. So i would like to temporarily set the permissions to READ WRITE while the backup takes place, but when it is finished leave the backup directory as READ only. If i use chmod on the whole thing it will take forever, or at least that much longer. I would like to avoid having to do this. My hope, and reason for posting, is that there is a way to invoke permissions only during the actual backup process.

I hope this provides a little clarification.

Thanks.