How to rename files without changing extension in Linux 102221.pdf to 102221_name.pdf

Question

How to rename files without changing extension in Linux \\

102221.pdf to 102221_name.pdf

Answer 1

ls * | sed -r 'p;s/\.pdf$/_name\.pdf/g' | xargs -n2 mv

list all the files with ls and pipe the output to sed. sed replaces .pdf with _name.pdf and outputs both the original file name and the new file name to xargs with will call mv with the 2 parameters.

you can also use the rename command which is simpler

 rename 's/\.pdf$/_name\.pdf/g' ./*

The regex pattern remains the same though