how to grep service directory in centos code example

Example 1: linux view services

service --status-all
service --status-all | more
service --status-all | grep ntpd
service --status-all | less

Example 2: how to check running services in linux

# For CentOS 7
systemctl
systemctl | more
systemctl | grep httpd
systemctl list-units --type service
systemctl list-units --type mount