Random command

Shell Programming and Scripting
1

I am trying to select one random word from a file, any ideas on how to do this as i have only manged to generete the random number?

2 
#!/usr/bin/ksh

# random_word.sh: selects one random word from a file
# usage: random_word.sh file_name

file_name=$1  # $file_name is the name of file that you select a random word
num_words=`wc -w $file_name | cut -d " " -f 1`

#echo $RANDOM
rand_word=`expr "$RANDOM" % $num_words + 1`

i=0
for word in `cat $file_name`
do
  i=`expr $i + 1`
  if [ $i = $rand_word ]
  then
     printf "$word"
     exit 0
  fi
done