Question

What is the best solution to appending new text after an existing block of text in a text file, using a BASH script?

for example, I have a config file with the following:

[setting1]

...

[setting2]

...

[setting3]

I want to add some text after [setting2], e.g.:

test1=data
test2=data
test3=data

Therefore, I want it to look like this after the script is run:

[setting1]

...

[setting2]
test1=data
test2=data
test3=data
...

[setting3]

Answer 1

You could do this with sed:

$ sed -e '/^\[setting2\]$/a\
test1=data\
test2=data\
test3=data' yourfile > yourfile.new

(note new lines immediately after the \ characters).

…or with the -i flag to modify the file in-place:

$ sed -i -e '/^\[setting2\]$/a\
test1=data\
test2=data\
test3=data' yourfile