Shell Programming and Scripting

Thanks to all

---------- Post updated at 10:05 PM ---------- Previous update was at 01:45 AM ----------

Thanks to all
i successfully resolved my problem with your help and guide.

But i got one new problem now.
Using diff and sdiff function i can get the the correct output in error.txt..
but when i execute the script file again later, the errors in error.txt are disappears and re-write it with new errors.
Is there any other way that i can keep adding my errors in my error.txt without deleting the previous error??
and of course the current error should be in top..

Hope i can find help in this matter..

If you want the current error to be in the top of the file,

You should try something like this.. This could be one of the crude ways to do..

Code:

$ cp Error.txt Error.txt.tmp
$ sdiff a b  | grep '<' >  a ## a is some temporary file.
$ cat a Error.txt.tmp > Error.txt

Using vimdiff command we can see the difference between the two files.

it will highlight the different lines in two windows.