How to append text in the beginning of each line using sed

<AppendNhere> A H W C
<AppendNhere> A H W C
<AppendNhere> A H W C

Sed '/^/ i N' filename

I tried appending N using this, but it's appending N to the beginning of new lines and not at the start of existing rows.

2 Answers

First, you need to understand "quoting" (see man bash) and regular expressions (man 7 regex) and use sed's (man sed "substitute" command.

sed -e 's/^/N/' filename

You can do this with

sed -e "s/^\(.*\)/N \1/" filename

This inserts the string N at the beginning of the line (^).