Pattern matching and format problem

Shell Programming and Scripting
1

Hi I need a bash script that can search through a text file and when it finds 'FSS1206' I need to put a Letter F 100 spaces after the second instance of FSS1206

The format is the same throughout the file I need to repeat this on every time it finds the second 'FSS1206' in the file

I have really not explained this very well but see example below, I need an F at that position. :wall:

or would it be easier to search for "71502FSS1206 FSS1206" and put a F 100 spaces after this rather than just search for a single instance of FSS1206?

71502FSS1206               FSS1206               000000000000200100000000000820009958170009958181200100005952

71502FSS1206               FSS1206               000000000000200100000000000820009958170009958181200100005952                       F
2

From the description I am not sure, if you mean a 2nd occurence in the same line or another line.
If it is meant per line, something like this might work:

$> cat infile
aa  FSS1206 vv
bb  something
aa  FSS1206 vv
aa  FSS1206 vv
completeley different
aa  FSS1206 vv
it seems
aa  FSS1206 vv
$ awk 'f && /FSS1206/ {print NR,$0,"F"; f=0; next} /FSS1206/ {f=1}' infile
3 aa  FSS1206 vv F
6 aa  FSS1206 vv F

The example input file is shorter so you can adjust the output of "F" with printf for example. I added NR to print the line number.
It will recognize every 2nd line that matches the pattern.

If it is meant per line, you can try this:

$ cat infile
aa  FSS1206 vv iquwegh2pg3FSS6uagwf777
aa  FSS1206 vv iquwegh2pg3FSS1206uagwf777
aa  FSS1206 vv iquwegh2pg3FSS1206uagwf777FSS1206
$ awk -F"FSS1206" 'NF==3 {print $0, "     F"; next} {print}' infile
aa  FSS1206 vv iquwegh2pg3FSS1206uagwf777

You can exeriment with printf for the "F" here too.

3

Try:

awk '$2=="FSS1206"{$0=$0"                       F"}1' infile > outfile
4

sorry for not explaining better, there are multiple instances FSS1206.

Would it be easier searching for

71502FSS1206               FSS1206

and place a letter F 100 spaces after every occurrence found within the file

Is this possible?

This didn't appear to do anything.

Thanks for all the help its appreciated.