Add a file extension to a bunch of file names
 

This should not be this hard :(

I have a considerable number of files in a subdirectory (some fascinating old military clips from archive.org - search on Big Picture if interested). Anyhow, I am downloading them using Internet Download Manager running in an XP virtual machine in VMWare on my Ubuntu 10.04 PC (due to the queuing, restart and speed capabilities of IDM). But I digress - the files are being saved on the host (Samba share) without a file extension.

So I have a collection of files with names like I wish to add the extension ".mp4" In Windows this is simply done with the command This of course does not work in Linux. I have researched the Linux rename command and reviewed a lot of examples. However, I have not found a way to add an extension to a batch of files which are named with no extension to start with. The spaces in the file names also seem to present an issue.

Any suggestions?

At the moment I am renaming them from the Windows VM while they are sitting on the Samba share using the ancient File Manager program from Windows NT which works great on XP. I have experimented with the file rename facility in Gnome Commander however, it does not seem to want to do something so simple.

TIA,

Ken

Not knowing whether there's any pattern to your file names
the safest bet is a loop.


Cheers,
Tink

Thanks Tink - that does the trick!

Ken

Or if using your rename in ubuntu:
Remove '-n' to make it happen.

Thanks grail but that does not seem to work - I did remove the -n.

Ken

Did it show output with -n still in?

No output with -n

So last sill question, you are running it in a directory with files that have dot and an extension?

I do not have any .extension files in the directory
When I execute the command as recommended Ken

This is the problem. And hence my mistake as I thought we were replacing extensions, but now that I have re-read your question properly, the following should work:
Sorry for the confusion

Thanks grail, that did the trick. As you have put so much effort into answering my question I feel obligated to take the time to understand what your command does.

I understand that -n tells rename to show what would be done but not to do it.
- and that s means to substitute the second expression .mp4 for the first.
- and the * means to match any file - that is to process all flies in the directory

However, the $ as me stumped. I understand that $ in a regular expression matches the (right hand) end of a string. In the example at hand I wish to concatenate .mp4 to the end of the file name, not replace the last character or characters with .mp4.

Well wait a minute. I reread the description of $. Since it matches the position at the end of the string - now that makes sense. The command is replacing the nothingness following the file name with .mp4 - exactly what I wished to do.

These simple things always trip me up - but give me something more complex like moving 80k engineering design documents for a nuclear power plant from one server to another while changing the file names and directory structure to comply with a new document management system convention and at the same time providing traceability of where the old files went and where the new files came from... a piece of cake. (Windows servers but what can I say - that is where the data was).

dump a "dir /s" to a text file
load the text file into a data table in Visual FoxPro
a little programming to generate the new path and file name and populate "new" fields in the table
write a few SQL commands to generate shell scripts to
- create an md5 digest of each original file in its original location and echo to a text file
- create the new directory structure on the receiving server
- copy the files to the new server and rename them on the fly
dumped dir /s on the new server to a text file
loaded that text file into the database
a little more sql to generate a script to generate the md5 digest of all files on the new server
loaded the before and after md5 data into tables, joined them and produced a report showing the old file name and location, old md5, matching new md5, new file name and location

The clients were amazed, I was bored. But let me come across something a simple as the situation we have been discussing and...

Thanks again,

Ken