osx - Bash adding a string to file name -

i need add word "hallo" @ end of each filename before extension in given directory. code produces no output. echo statements give no output , file names not changed

count="" dot="." file in $ls       echo $file     count=""     f in $file           echo $f       if [ $f -eq $dot ];               count=$count"hallo"       fi       count=$count+$f     done     mv $file $count   done 

with bash can done simplier like:

for f in *;do echo "$f" "${f%.*}hallo.${f##*.}" done 

example:

$ ls -all -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file1.txt -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file2.txt -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file3.txt -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file4.txt -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file5.txt   $ f in *;do mv -v "$f" "${f%.*}hallo.${f##*.}";done 'file1.txt' -> 'file1hallo.txt' 'file2.txt' -> 'file2hallo.txt' 'file3.txt' -> 'file3hallo.txt'  $ ls -all -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file1hallo.txt -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file2hallo.txt -rw-r--r-- 1 29847 29847    0 aug 21 14:33 file3hallo.txt 

this works because ${f%.*} returns filename without extension - deletes (*) end (backwards) first/shortest found dot.

on other hand 1 ${f##*.} deletes beginning longest found dot, returning extension.

to overcome extensionless files problem pointed out in comments can this:

$ f in *;do [[ "${f%.*}" != "${f}" ]] && echo "$f" "${f%.*}hallo.${f##*.}" || echo "$f" "${f%.*}hallo"; done file1.txt file1hallo.txt file2.txt file2hallo.txt file3.txt file3hallo.txt file4 file4hallo file5 file5hallo 

if file has not extension yeld true "${f%.*}" == "${f}"

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