[SOLVED] sed c command with full capture group

Issue

I have read through dozens of sed questions, none of them are related to what I'm trying to do. I am using the sed c command to match multiple lines within a file, but I need the contents between the two sections.

a
begin
c

d

end
f
...

I need to capture the 2 lines c and d in this example and remove the new lines between, and use them in the output, but nothing I have tried or can find allows me to capture from the match expression.

With some pseudocode containing \1 for the capture group output:

cat file | sed -e '/begin/,/end/c\begin\n\1\nend'

This should produce

a
begin
c
d
end
f
...

And I need it to not execute if a match is not found.

I don't know if sed is the right tool for the job, but it may be just 1 step outside of its use case. I'm open to alternatives.

Solution

One approach would be:

sed '/begin/,/end/{ /^$/d; }' file

Answered By - M. Nejat Aydin

Answer Checked By - Candace Johnson (WPSolving Volunteer)