Join all files in a directory

Question

How can I join all of the files in a directory. I can do it in one step by explicitly naming the files below, is there a way to do it without explicitly naming the files?

Answer 1

#!/bin/bash

data=
for f in "${rpkmDir}"/HS*.chsn.rpkm
do
  if [ ! "$data" ]
  then
    data="$(sort "$f")"
    continue
  fi
  data="$(join <(sort "$f") /dev/stdin <<< "$data")"
done
echo "$data"