Shell Programming and Scripting

The original attempt does not use the append command correctly. You cannot embed it in the replacement portion of a substitute command.

In subsequent suggestions, the use of \n in the replacement text is a non-portable extension (most commonly found on gnu/linux systems).

To add 'hoi' on a line by itself after a line with the word "ERROR", the simplest way would be to use the append command:

Code:

sed '/ERROR/a\
hoi\
' file

You could also accomplish this task with the substitution command:

Code:

sed '/ERROR/s/$/\
hoi/' file

Too insert a newline immediately after the word "ERROR" and immediately after "hoi", you can use this substitution:

Code:

sed 's/ERROR/&\
hoi\
/' file

My suggestions should be portable. They use a backslash-escaped literal newline to insert a newline. \n won't always work.

Regards,
Alister