Вот решение bash
.
for file in /path/to/*; do
nname="${file%%.*}.mp3" # strip last part of file till first . seen
echo mv "$file" "${nname//dig/cur}" # replace 'dig' with 'cur'
done
С mmv
все намного проще.
mmv '*_*_*.*' '#1_cur_#3.mp3'
Или с zmv
:
zmv -w '*_*_*.*' '$1_cur_$3.mp3'