Shell Programming and Scripting

Hello,

I am not a frequent user of Unix. With my little knowledge and some scrambling I was able to get to this point .. please help me get this right. I have 2 files

file1.txt
123AAAAA111111111111111
456BBBBBB222222222222222222
789CCCCC33333333333333333

file2.txt
AAAAA11111
BBBBB22222
CCCCC33333

my output file should be from file1 with the following manipulations -- search for string pos 4-8 from file 1 in file 2 and replace with string pos 6-10 from file 2. File 1 is fixed width columns but variable record lengths (last columns could be null for some records)

output.txt
12311111111111111111111
45622222222222222222222222
7893333333333333333333333


#!usr/bin/ksh
while read myline
do
A=`awk '{print substr($myline, 1, 3)}'`
B=`awk '{print substr($myline, 4, 5)}'`
C=`awk '{print substr($myline, 9)}'`
sub=`grep $B file2.txt | awk '{print substr($0,6)}'`
echo "${A}${sub}${C}" >> output.txt
done < file1.txt

The error that I get is "grep unable to open AAAAA". The output file is written but the substitution happens for only one record.

Thanks.

could you please post this question with better sample data?

the example is not quite clear enough.

your script has numerous errors to the point where it cannot be fixed,
so we'll need to start fresh.

some relevent questions:

+ are the files sorted according to the 4-8 column positions?
+ are the matching lines unique between the 2 files?
+ same number of lines per file?
+ 1 to 1 match line per line or scrambled?

here's what i'm thinking you want:

filea:
xxxxAAAAisforaardvark
yyyyBBBBisforbasilisk
zzzzCCCCisforchameleon

fileb:
AAAAisactuallyforant
BBBBisactuallyforbat
CCCCisactuallyforcat

output:
xxxxAAAAisactuallyforant
yyyyBBBBisactuallyforbat
zzzzCCCCisactuallyforcat

does this look right?

I am newbie to shell scripting
i have made the following can somefix this:

Code:

nawk -v f1str=$(substr($0,4,8) -v f2str=$(substr($0,1,5) 'FILENAME="file1.txt"  {array[m++]=$f1str} FILENAME="file2.txt" { if (array[f2str]) {print $0}}' file1.txt file2.txt > file3.txt

Thanks for your response.

My output should look like:

output:
xxxxisactuallyforantisforaardvark
yyyyisactuallyforbatisforbasilisk
zzzzisactuallyforcatisforchameleon

AAAA, BBBB, CCCC in filea should be substituted with lookup values from fileb.

Appreciate your help.

Try this:

Code:

awk 'NR==FNR{a[substr($0,1,4)]=substr($0,5);next}
substr($0,5,4) in a {print substr($0,1,4) a[substr($0,5,4)] substr($0,9)}
' fileb filea

Use nawk or /usr/xpg4/bin/awk on Solaris if you get errors.

Regards

Thank you Franklin. Your code worked fine for me. thanks to zenith and quirk as well ...

just one more question on this .. how do I modify the script to get those rows which are skipped if no match is found ..