Shell Programming and Scripting

When i try to vi a file, see some extra characters "l^H^@^@^@^@^F^@"...but when i cat the same file i am not seeing this...How do i remove this???

Those are control characters that vi interprets and displays, but which have no printable equivalent so you do not see them via cat.

If you are in vi, just position over the "^" and press "x" to delete.

---------- Post updated at 02:28 PM ---------- Previous update was at 02:24 PM ----------

This chart shows control characters if you are wondering what those characters are. i.e. ^H = CTRL-H which is a backspace.
ASCII Table - Control characters

This is clearly not a normal unix text file. Before considering any processing in unix text file manipulation utilities such as vi please look at the source of the data and consider whether it can be presented in the form of a unix text file.
The data presented looks like a database binary file and is therefore unsuitable for editing with unix text file utilites.
What software wrote this file? Can the data be extracted as a unix text file?

Please also post what Operating System and version you are running and what Shell you prefer.

Excellent point. I was going under the assumption there were extraneous characters in a normal text file that were not expected to be there since cat seemed to display the file as expected.

Make sure you are not trying to edit a data file or an executable file if its origin is unknown. The file command may be useful in investigating.

Do you need the characters if you do a cat -v filename > filename2?