Use pgrep with regex patterns to identify specific processes and command line flags

pgrep-regex-example.txt

Use the following pattern for `pgrep` to identify a running process that contains specific commandline parameters

Note the following pgrep options are needed:
-a, --list-full           list PID and full command line
-f, --full                use full process name to match
-c, --count               count of matching processes


To find a specific process with a specific commandline parameter use the following:
pgrep -a -f "{processname}.*{commandline param}"

For example:
# This will likely return a number of results
pgrep -a -f "systemd"

# This will identify any instances of systemd where the --user commandline parameter was passed
pgrep -a -f "systemd.*user"
12207 /lib/systemd/systemd --user

To return the count of the number of running processes that match the pattern, add the -c option
For example:
pgrep -a -f -c "systemd.*user"
1

pgrep -a -f "you-wont-find-this-process"
0