Delete Empty Files

 find . -type f -empty -print -delete  # find . -size 0 -delete
  find . -maxdepth 1 -type f -empty -print -delete
 find . -type d -empty -print -delete
 

Casse variable

 name='jean luc est grand'
 echo ${name^^} # ${name^} uniquement la 1ere lettre
    JEAN LUC EST GRAND