I'm trying to create a macro for Keyboard Maestro for OS X doing the following:

1. Get name of newest file in a directory on my disk based on date created;
2. Paste the text "newest file: " plus the name of the newest file.

One of its options is to "Execute a shell script", so I thought that would do it for 1. After Googling around a bit I came up with this:

cd /path/to/directory/
ls -t | head -n1

This sorts it right, and returns the first filename. However, it also seems to includes a line break, which I do not want. As for 2: I can output the text "newest file: " with a different action in the app, and paste the filename behind that. But I'm wondering if you can't return "random text" + the outcome of the ls command.

So my question is: can I do this only using the ls command? And how do I get just the name of the latest file without any linebreaks or returns?