Bash input for multiple file

Question

I have thousands of two set of files one with name.ext and another files name ending with name.ext.in, so for every name.ext there is a name.ext.in and now i have to pass this a

Answer 1

Judging from the comments to the other answers, you probably want something like this:

for file in *.ext; do
    customise.pl "$file" "${file%.*}.new.psl"
done

The ${file%.*} syntax substitutes only the part of $file up until its last dot. You can check the manpages for Bash or Dash for more information on it if you need.