Shell Programming and Scripting

What I really need is a script that compares 2 (.csv) text files line by line with a single entries on each line and then outputs NON-duplicate lines to a third (.csv) text file, the problem is the lines may be exactly the same, but in different order in the 2 text files, so

sourcefile1 contains
bob
jane
sally

sourcefile2 contains
sally
bob

output to > file3 containing
jane

I've tried using:

Code:

grep -vxf sourcefile1 sourcefile2 > file3

but I get no output, because the lines are in different order? if I do:

Code:

comm -13 sourcefile1 sourcefile2 > file3

I get error: "file 1 is not in sorted order", but sorting it doesn't seem to help. I was thinking about writing a loop that said something like:

Code:

cat sourcefile1 | while read LINE
do
      cat sourcefile2 | while read LINE2
      do
             if [ "$LINE2" = "$LINE" ]
             then
                   exit
             else
                   echo $LINE > file3
             fi
      done
done

but I don't know if my logic is right (I'm sure my syntax is wrong), and it seems like an inefficient way to do it, are there better/more elegant ways to do this?

Replace the order of the files:

Code:

grep -vxf sourcefile2 sourcefile1 > file3

I think the best approach would be this:

Code:

grep -vxf sourcefile2 sourcefile1 > file3
grep -vxf sourcefile1 sourcefile2 >> file3

We need to do it both ways since there can be unique entries in each file.

If there's a possibility of a name containing a regular expression metacharacter (such as a dot following an initial, for example), to strictly match an entire line with grep, you'll want to use -xF along with whatever other options the logic of the solution demands.

Regards,
Alister

Code:

#!/bin/ksh
              
        
while read name            
do                         
  grep $name $2 >/dev/null
  if [ "$?" != "0" ]       
  then                     
     echo $name            
  fi                       
done <$1

./script source1 source2

What about lines in source2 that are not in source1?

run the script above as ./script source2 source1