Bash multiple files processing

Question

I have a file named data_file with data: london paris newyork italy...50 more items

Have a directory with over 75 files, say dfile1, dfie2...afle75 in which i am perform

Answer 1

Using GNU Parallel you can do something like this:

doit() {
    f="$1"
    line="$2"
    found=$(grep $line $f)      

    if [ ! -z "$found" ]; then
      perform task here
    fi
}
export -f doit

find . -type f | parallel doit :::: - data_file