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Log system messages

Note: You must be root to run this daemon.


syslogd [-f config_file] [-m mark_interval]
        [-t threads]

Runs on:



-f config_file
Specify the pathname of an alternate configuration file (the default is /etc/syslog.conf).
-m mark_interval
Select the number of minutes between “mark” messages (the default is 20 minutes).
-t threads
Set the maximum number of threads that syslogd should use (the default is 15).


The syslogd daemon reads and logs messages to the system console, log files, and other machines as specified by its configuration file.

The daemon reads its configuration file when it starts up and whenever it receives a hangup signal. For information on the format of the configuration file, see /etc/syslog.conf.

The messages sent to syslogd should consist of a single line, which may start with a facility/priority (as defined in <syslog.h>) in angle brackets (e.g. "<5> hello"). If the message doesn't specify a priority, it defaults to LOG_USER|LOG_NOTICE ("<13>").

The syslog() API (and the logger utility, which uses syslog()) sends messages to syslogd by opening and writing to /dev/log.


The syslogd daemon requires the following files:

This configuration file contains the selection criteria and the action to be taken if a message received by syslogd matches the selection criteria.
This file specifies the Internet domain socket port that syslogd listens to.

The syslogd daemon also requires the shared library.

Environment variables:

Used by clients to specify which node to look for syslogd.

See also:

logger, /etc/services, /etc/syslog.conf

syslog() in the Library Reference