I wrote a simple, completely random, monoalphabetic cipher program. Basically swaps one letter for another. The output comes as one big block of jumbled letters. (examples below) I want to get some specifig formatting on the output to make it look neater. I imagine this would probably be done with awk/sed (hopefully a one liner) The output I get now is something like: nalhdfthlxgvatxrayadoxguonynoadhtirgxawdfynaxgnghcluxracfdhtngyfdfkdsraid I would like the output to appear as: nalhd fthlx gvatx rayad oxguo nynoa dhtir gxawd fynax gnghc luxra cfdht ngyfd fkdsr aid If you could help me out it would be greatly appreciated. thanks in advance.

Ok I discovered that: sed -e "s/...../& /g" works, but only for smaller files. Does anyone have a solution that will work for larger 100K+ files?

perl -pi -e 's/\G(.{0,5})/$1 /g' cipher.txt

your example shows no spaces. If you are swapping letters, what happens to spaces and other punctuation?

I get rid of spaces by default, however if you wish to retain them, I created a -formatting tag. FishMonger, thank you, I shall try that out.