i have two file e.g cmp1 and cmp2
cmp1 has abcdef and cmp2 has abcdefghijkl

cmp1 has:
a
b
c
d
e
f

cm2 has:
a
b
c
d
e
f
g
h
i
j
i want a script which will check if cmp1 content is same as in cmp2
then it should send a mail without caring about extra thingspresent in cmp2

=================
My Question was slightly different..

Actually i want while comparing between cmp1 and cmp2 if script will find the content of cmp1 is available in cmp2 ...then it will return pass...........

diff file1 file2 > /dev/null

if [[ $? -ne 0 ]]
then
echo "Differences Found"|mailx -s "Diff found" to-email
fi

This may do it.

if (( $(comm -23 cmp1 cmp2 | wc -l) > 0 ))
then
  #cmp1 has something not in cmp2, so act on that
 else 
  #cmp1 does not have anything not already in cmp2
  #so act on that
fi

you can put a tee in the pipeline between the comm and
wc command if you want to save the differences to a file
name of your choice for use in processing in the body of
the 'if' statement.