Last Updated: 2024-04-17

Conventionally, daemon process names end with the letter "d".

If you’re interested in seeing all daemons installed on a Linux machine with service (pretty common nowadays), here's how:

service --status-all

Example output:

 [ - ]  acpid
 [ + ]  apparmor
 ...
 [ + ]  ssh
 [ + ]  sysstat
 [ + ]  udev
 [ + ]  ufw
 [ + ]  unattended-upgrades
 [ ? ]  unicorn
 [ - ]  uuidd
 [ - ]  x11-common

Rules for daemonization under systemd

• don't write PID files
• don't fork/double fork. Run your main event loop in the process systemd starts for you
• don't call setsid
• send SIGTERM to shut down your daemon
• logging to STDOUT and STDERR should go to system journal

Resources

• http://0pointer.net/blog/projects/systemd.html