find string in file (need to be improved)

maybe it will be useful when we want to find a variable in a directory.

target=$1
traversal(){
    cd "$1"
    for x in *
    do 
      if [ -f $x ]
      then
        #echo $x
        grep $target $x>null
        if [ $? = 0 ]
        then
          echo $PWD/$x
        fi
      fi
      if [ -d $x ]
      then
        traversal "$PWD/$x"
      fi
    done
}
traversal $PWD

use like this

./a.sh call