egrep
Find patterns in files using extended regular expression (supports ?, +, {}, () and |). More information: <https://manned.org/egrep>.
RUN apt-get update && \
apt-get install -y grep
RUN apt-get update && \
apt-get install -y grep
RUN apk add grep
RUN pacman -S --noconfirm grep
RUN apt-get update && \
apt-get install -y grep
RUN yum install -y grep
RUN dnf install -y grep
RUN apt-get update && \
apt-get install -y grep