grep -A1

grep -A1 XXX | grep -v XXX

awk '/XXX/{getline; print}' file.txt
awk '/unattended-upgrade/{getline; print}' /var/log/apt/history.log

grep -B

See also

• ack, ag, ripgrep, grep, egrep, fgrep, agrep, ngrep, pgrep, awk, sed, strings, tr, tail, mtail, git grep, wc, uniq, LogQL, findstr (Windows), rg, git-grep, cut