renaming files or adding a name in the beginning of all files in a folder

Shell Programming and Scripting
1

Hi All

I have a folder that contains hundreds of file with a names

3.msa
4.msa
21.msa
6.msa
345.msa
456.msa
98.msa
...
...
...

I need rename each of this file by adding "core_" in the begiining of each file such as

core_3.msa
core_4.msa
core_21.msa
core_6.msa
core_345.msa
core_456.msa
core_98.msa

Please let me know the best way to peform this filename change in a folder.

LA

2 
shopt -s nullglob
for f in *.msa
do
  echo mv "$f" "core_${f}"
done
3

Thanks, but it is not working. It just writes mv commands but not executing. Let me know what might have occurred

4

if the code is successful, remove the echo from it.

5 
for i in `ls *.msa`
do
  mv $i core_$i
done