UNIX for Dummies Questions & Answers

hi ..
i m in gr8 confusion
for eg
two number of files 1 & 2
1 contains following
a
b
c

2 gives
a
b
d
e
on executing following command
diff 1 2 | grep ">" | sed 's/>//g' >output.dat

in output.dat i get following data
d
e
but my main motive is to compare 2 files line by line and generate output until i come to end of line of file 1
i.e. here 1 has 3 lines n 2 has 4 lines ... it should compare line by line for 3 lines and NOT 4 lines and pick up the modified data from file 2

i want the output to be
d
and NOT
d
e

please help me out ... urgent
thanx a ton

just to understand the problem:
what if

file1
-------
a
b
c
f
g
h

file2
---------
a
b
d
e
f
h

what should the output be ?

d
e
f

??

yes u r absolutely right it should be
d
e
f
since here both file1 and file1 have same number of rows so row wise comparison is done for each line and if there is any variance the data from file2 has to be picked up from the modified line

Code:

awk 'FNR==NR {a[NR]=$0} FNR!=NR {if(a[FNR]!=$0) print a[FNR]}' file2 file1