Shell Scripting – How to Rename Multiple Files by Replacing Word in File Name

On Windows, I use the excellent (and free) ReNamer tool.

Screenshot below demonstrates how to do your example operation with 2 simple Replace rules, but you can also use Regular Expressions if you want.

You could use rsync with the --ignore-existing switch:

   skip updating files that exist on receiver

However, I think this is not atomic. You can create advisory locks with flock to make sure the processes you control (Cooperating processes) won't write to it. But another process still could.

The only way you can lock a file without the risk of a another process messing with it is to mount the filesystem with mandatory locking. From <linux_kernel_source>/Documentation/filesystems/mandatory-locking.txt:

What is mandatory locking?

Mandatory locking is kernel enforced file locking, as opposed to the more usual cooperative file locking used to guarantee sequential access to files among processes. File locks are applied using the flock() and fcntl() system calls (and the lockf() library routine which is a wrapper around fcntl().) It is normally a process' responsibility to check for locks on a file it wishes to update, before applying its own lock, updating the file and unlocking it again. The most commonly used example of this (and in the case of sendmail, the most troublesome) is access to a user's mailbox. The mail user agent and the mail transfer agent must guard against updating the mailbox at the same time, and prevent reading the mailbox while it is being updated.

In a perfect world all processes would use and honour a cooperative, or "advisory" locking scheme. However, the world isn't perfect, and there's a lot of poorly written code out there.