Shell Programming and Scripting

I have a data file. I want to write a shell script that reads a data file and reads position 19 thru 24. if the data in those fields is 002006, than it should change it to 002007.

example:

hello world hello 002006 hello world hello world
hello world hello 002005 hello world hello world
hello world hello 002006 hello world hello world
hello world hello 002006 hello world hello world

The script should change all the 002006 to 002007.....
let me know if any questions

thanks

while read str
do
first=`echo $str | cut -c 1-18`
middle=`echo $str | cut -c 19-24`
last=`echo $str | cut -c 25-`
if [ $middle = "002006" ]
then
middle="002007"
fi
echo $first$middle$last >>temp
done < file
mv temp file

or

Changes first occurence of 002006
sed 's/002006/002007/' file >temp
mv temp file

do you think
this will work

#!/bin/ksh

for i in view v_update_2007.dat

do

curmonth = `view v_update_2007.dat | cut -c89-94`;

if [ $curmonth == '002006' ] then
curmonth = 002007;
exit 1
fi
done

I am getting an error message which says , at line 12 fi is unexpected.
what could be wrong??

Use "=" instead of "==" in [ $curmonth == '002006' ].

Now I am studying what can be wrong, but although that program function, it does not resolve the problem you have, because first you asing a value for your var and then you change the value, but you never touch your file.

It has to be in ksh or it could be in bash, i wait your answer, and excuse me my english is too bad too.

it has to be in ksh

Hi guys, this looks a lot like homework doesn't it? Having to satisfy specific requirements, no real-world application... homework. Thread closed.