Syslog() generates a log message that will be distributed by the system logger. priority is a combination of the facility and the level, values for which are given in the next section. The remaining argument is the message to send, except that the two characters %m will be replaced by the error message string (strerror) corresponding to the present value of errno.
Table 1. Syslog() Priorities (in descending order)
Constant | Description |
---|---|
LOG_EMERG | system is unusable |
LOG_ALERT | action must be taken immediately |
LOG_CRIT | critical conditions |
LOG_ERR | error conditions |
LOG_WARNING | warning conditions |
LOG_NOTICE | normal, but significant, condition |
LOG_INFO | informational message |
LOG_DEBUG | debug-level message |
syslog.conf(5) Unix manual page. More information on the syslog facilities and option can be found in the man pages for syslog(3) on Unix machines.
On Windows NT, the syslog service is emulated using the Event Log.
See also define_syslog_variables(), openlog() and closelog().