Hi, I have a problem with read line. My code is something like while read line do ((ncnt+=1)) result=`expr $cnt - $ncnt` echo "$line" case "$line" in PYFT*) if [[ $result -ne 1 ]] then echo "$line2" echo "$line1" fi ;; esac done <$inputfilename >> ${BaseDir}/Temp in the $line after while read line, some of the lines have trailing tab spaces and some does not. so when i am reading the lines and writing it to another file, I am losing them. I am not really sure which of the lines would have tab spaces and which of them does not have. So Please help.It is kind of very urgent, as we have to implement this in our business. Thanks in advance.

First, this statement, tells me you are using a ksh/bash type shell: ((ncnt+=1)) So, why are you performing arithmetic like this: result=`expr $cnt - $ncnt` Why don't you use parenthesis and save the call to expr: cnt=8 ncnt=9 result=$(($cnt+$ncnt)) echo $result Second, in order to hold onto the trailing tabs, you might consider changing the field separator to a character that is not used: #!/bin/ksh while IFS="&" read line do echo "$line" done < d4.txt

Hi nails, I am not an UNIX expert. I am actually fron TIBCO background. We have to insert header and trailer after every second trailer. You have given me the solution on this :) . My code goes, #!/usr/bin/sh inputfilename=$1 cnt=$(wc -l <$inputfilename) echo $cnt line1=`grep ^HDR<$inputfilename` line2=`grep ^TRL<$inputfilename` while read line do ((ncnt+=1)) result=`expr $cnt - $ncnt` echo "$line" case "$line" in PYFT*) if [[ $result -ne 1 ]] then echo "$line2" echo "$line1" fi ;; esac done <$inputfilename >> outputfile.txt exit 0 My file is something like, HDR --- --- 2HDR ---- ---- ---- ----- ---- PYFT --- ---- 2HDR --- --- --- --- --- PYFT -- --- 2HDR -- --- -- --- PYFT ---- --- TRL ----- ---- some of these lines having trailing tabs and spaces. And expected output is HDR --- --- 2HDR ---- ---- ---- ----- ---- PYFT --- ---- TRL ----- ---- HDR --- --- 2HDR --- --- --- --- --- PYFT -- --- TRL ----- ---- HDR --- --- 2HDR -- --- -- --- PYFT ---- --- TRL ----- ---- some how my business req does not allow me to use awk or sed. Please help. Thanks in advance,

I have one more problem also in the above code. after the last PYFT, the last line TRL is not written from the inputfilename but the TRL and HDR are inserted even after the last PYFT. So can you please let me know where i am going wrong.