LOGGER(1) LOGGER(1) logger - logger [] logger . . -f . -d --udp (UDP) . syslog /etc/services 514. --server --socket . -e --skip-empty . . . --prio-prefix . ( <13>). -f --file . . -i (PID) logger . --id[=] (PID) logger . logger. --id=$$ ( PPID) . ( systemd /dev/log) (PID) . logger(1) . --journald[=] systemd. . journald systemd.journal-fields(7) . MESSAGE_ID . : logger --journald < --journald (priority). PRIORITY. journalctl(1) MESSAGE. journalctl --output json-pretty . MESSAGE MESSAGE . . --msgid - MSGID RFC 5424 . -. --rfc5424 . -n --server . --udp --tcp logger UDP TCP. --no-act . --stderr . --octet-count RFC 6587 . UDP RFC6587 ( ) TCP. -P --port . syslog udp syslog-conn tcp. -p --priority . facility.level. -p local3.info local3. user.notice. --prio-prefix . . 8 . local0.info =16 =6 <134>. -p. -p. . logger (: daemon | logger --prio-prefix) . --rfc3164 BSD RFC 3164 . --rfc5424[=without] RFC 5424 . without : notq notime nohost. notq . . --sd-id timeQuality. notime ( notq) ISO-8601 . nohost gethostname(2) . RFC 5424 logger 2.26. -s --stderr . syslog journald . --no-act. --sd-id [@] RFC 5424. --sd-param . . ( @ ) . . @ . logger timeQuality . RFC 5424 origin ( ip enterpriseId software swVersion) meta ( sequenceId sysUpTime language). @. --sd-param = . --sd-id . . logger --rfc5424 --sd-id zoo@123 \ --sd-param tiger="hungry" \ --sd-param zebra="running" \ --sd-id manager@123 \ --sd-param onMeeting="yes" \ "this is message" : <13>1 2015-10-01T14:07:59.168662+02:00 ws kzak - - [timeQuality tzKnown="1" isSynced="1" syncAccuracy="218616"][zoo@123 tiger="hungry" zebra="running"][manager@123 onMeeting="yes"] this is message -S --size . 1KiB RFC 3164. RFC 5424 . RFC 5424 4KiB . 1KiB syslog. --size logger ( --rfc5424). : syslog. . 50 80 . . 2 4 KiB . --socket-errors Unix. on off auto. auto () logger systemd(1) /dev/log . /dev/log openlog(3). logger(1) 2.26 openlog(3) Unix. logger(1). -T --tcp (TCP) . syslog-conn /etc/services 601. --server --socket . -t --tag . ( ). -u --socket . -- . (-). -h --help . -V --version . logger 0 0 . : auth authpriv cron daemon ftp kern user lpr mail news syslog user uucp local0 local7 security auth : emerg alert crit err warning notice info debug panic emerg error err warn warning syslog(3). logger IEEE Std 1003.2 ("POSIX.2"). logger logger -p local0.notice -t HOSTIDM -f /dev/idmc logger -n loghost.example.com System rebooted logger 1983-1993 Karel Zak Rainer Gerhards Sami Kerola . journalctl(1) syslog(3) systemd.journal-fields(7) . logger util-linux . util-linux 2.42.1 2026-05-18 LOGGER(1)