handling null values in files

Shell Programming and Scripting
1

Hi ,

I have a script where i will remove header and trailer record and ftp to another server.

I'm using the code:

latestfilename=`ls filename_* | tail -1`
echo "Latest filename = $latestfilename"
sed '1d;$d' $latestfilename > a.ftpedfile

I have an issue if input data is having null values.The data looks like this:

Input record has :00223715232238200 N NULL 1999031920000707 abc *

In place of NULL i have a null.

MY output is :

00223715232238200 N 1999031920000707 abc *

The record is shifted.

Please advice how to transfer null as it is.And also please let me know if i ftp the file with null values the values should not be dropped.

Thanks in advance!

2

The "sed" command should not alter lines that were not selected.

However, FTP may "help" you by converting text files. If the files are transferred as binary instead of ASCII, then they shall remain unmodified.