Formatting grep output with blank line between two occurrences-CodePudding

I'm looking to format my output this way, but with appropriate, more graceful code.

In file:

line with foo occurence
line with foo occurence
line with bar occurence
line with bar occurence
line with foo occurence
line with foo occurence

My bash command:

cat file | grep -e foo && printf '\n' && cat file | grep -e bar

And result:

line with foo occurence
line with foo occurence
line with foo occurence
line with foo occurence

line with bar occurence
line with bar occurence

CodePudding user response：

You can try this paste command with grep

paste -zd'\n' <(grep 'foo' input_file) <(grep 'bar' input_file)
line with foo occurence
line with foo occurence
line with foo occurence
line with foo occurence

line with bar occurence
line with bar occurence

CodePudding user response：

How about running the grep command in a loop:

for term in foo bar
do
    grep $term file
    echo  # Add a blank line
done

The above as a one-liner:

for term in foo bar; do grep $term file; echo; done