have you considered using sam to break each line into multiple lines and then rejoining. e.g. if you have a | separated record structure, you could do something like:
,x/^.*\n/ {
s/\|/\n/g
s/\n/\n\n/
}
edit the fields, then rejoin before writing it back:
,y/\n\n/ x/\n/ c/|/
,x/\n\n/ c/\n/
fyi, i'm a casual sam user and there are probably better ways.
