Hi,
I have a shell scripting. This will take 7 digit number in each line and add 7 digit number with next subsequent lines ( normal addition ).

Eg:

0000001
0000220
0001235
0000022
0000023
...........
.........
........


Like this i am having around 1500000 records. After adding , I am getting the result 2147483647 but actual result is 2156379608 . I found the root cause of this issue is that Unix temproary variable can hold only 2156379608 ( Range of integer ) as it's 32 bit. For eg:

a=2147483647
expr $a + 2

you will get the negative result. Because while expr working, the result will be stored in internal temporary variable or register then you will get the result.. but that particular temporary variable or register can accomodate only 2147483647 .. if it crosses this limit, you may get the junk value like -ve values... this is my finiding for this issue.. But I want to have resolution for this issue. how to add or do arthimatic opration if i want to have result more than limit ( 2147483647 ). I mean

a=2147483647
expr $a + 2

for this i need to get the right result rather than -ve value.