Linux pgrep Query Process Tool

The Linux pgrep tool pgrep is used to query processes by program names. It is generally used to determine whether a program is running. In server configuration and management, this tool is often used, simple and clear; usage: # ps parameter option program name common parameter-l list program name and process ID; -o process start ID;-n Process Termination ID; example: [root @ localhost ~] # Pgrep-lo httpd4557 httpd [root @ localhost ~] # Pgrep-ln httpd4566 httpd [root @ localhost ~] # Pgrep-l httpd4557 httpd4560 httpd4561 httpd4?httpd4563 httpd4564 httpd4565 httpd4566 httpd [root @ localhost ~] # Pgrep httpd45574560456145624563456445654566