How to rename multiple files

Question

I have files with names as,

A2002185.h23v04.005.2007177004246.hdf  
A2002201.h23v04.005.2008288062542.hdf

I want to rename them by deleting everything in the name after first dot (and have names as A2002185.hdf, A2002201.hdf), how can I do that?

Answer 1

Using prename (rename is a symlink to this by default on many systems):

prename -n 's:\..*\.:.:' *.hdf

The -n will print the actions that will be taken without doing anything. Once you are sure you have what you want, remove it.

Answer 2

Run the below script from the folder where you have all these files.

for f in *.hdf; do mv -- "$f" "${f%%.*}".hdf ; done

The above script checks for all files with hdf extension inside the current directory and for each file, it removes the characters after the . character and adds the extension as .hdf