Return PIDs of any running processes with a matching command string
pgrep {some_process}
Search full command line with parameters instead of just the process name
pgrep -f "process_name parameter"
Search for process run by a specific user
pgrep -u root process_name
Kill all processes which match:
pkill -9 process_name
Kill all processes which match their full command instead of just the process name:
pkill -9 -f "command_name"
Send SIGUSR1 signal to processes which match:
pkill -USR1 process_name