Renaming part of a filename

I have loads of files which look like this:

DET01-ABC-5_50-001.dat
...
DET01-ABC-5_50-0025.dat

and I want them to look like this:

DET01-XYZ-5_50-001.dat
...
DET01-XYZ-5_50-0025.dat

How can I do this?

There are a couple of variants of a rename command, in your case, it may be as simple as

rename ABC XYZ *.dat

You may have a version which takes a Perl regex;

rename 's/ABC/XYZ/' *.dat

for file in *.dat ; do mv $file ${file//ABC/XYZ} ; done

No rename or sed needed. Just bash parameter expansion.

Something like this will do it. The for loop may need to be modified depending on which filenames you wish to capture.

for fspec1 in DET01-ABC-5_50-*.dat ; do
    fspec2=$(echo ${fspec1} | sed 's/-ABC-/-XYZ-/')
    mv ${fspec1} ${fspec2}
done

You should always test these scripts on copies of your data, by the way, and in totally different directories.

You'll need to learn how to use sed http://unixhelp.ed.ac.uk/CGI/man-cgi?sed

And also to use for so you can loop through your file entries http://www.cyberciti.biz/faq/bash-for-loop/

Your command will look something like this, I don't have a term beside me so I can't check

for i in `dir` do mv $i `echo $i | sed '/orig/new/g'`

I like to do this with sed. In you case:

for x in DET01-*.dat; do
    echo $x | sed -r 's/DET01-ABC-(.+)\.dat/mv -v "\0" "DET01-XYZ-\1.dat"/'
done | sh -e

It is best to omit the "sh -e" part first to see what will be executed.

All of these answers are simple and good. However, I always like to add an interactive mode to these scripts so that I can find false positives.

if [[ -n $inInteractiveMode ]]
then
    echo -e -n "$oldFileName => $newFileName\nDo you want to do this change? [Y/n]: "
    read run

    [[ -z $run || "$run" == "y" || "$run" == "Y" ]] && mv "$oldFileName" "$newFileName"
fi

Or make interactive mode the default and add a force flag (-f | --force) for automated scripts or if you're feeling daring. And this doesn't slow you down too much: the default response is "yes, I do want to rename" so you can just hit the enter key at each prompt (because of the -z $run test.