16.15 syslog -- Unix syslog library routines

Availability: Unix.

This module provides an interface to the Unix syslog library routines. Refer to the Unix manual pages for a detailed description of the syslog facility.

The module defines the following functions:

syslog( [priority,] message)
Send the string message to the system logger. A trailing newline is added if necessary. Each message is tagged with a priority composed of a facility and a level. The optional priority argument, which defaults to LOG_INFO, determines the message priority. If the facility is not encoded in priority using logical-or (LOG_INFO | LOG_USER), the value given in the openlog() call is used.

openlog( ident[, logopt[, facility]])
Logging options other than the defaults can be set by explicitly opening the log file with openlog() prior to calling syslog(). The defaults are (usually) ident = 'syslog', logopt = 0, facility = LOG_USER. The ident argument is a string which is prepended to every message. The optional logopt argument is a bit field - see below for possible values to combine. The optional facility argument sets the default facility for messages which do not have a facility explicitly encoded.

closelog( )
Close the log file.

setlogmask( maskpri)
Set the priority mask to maskpri and return the previous mask value. Calls to syslog() with a priority level not set in maskpri are ignored. The default is to log all priorities. The function LOG_MASK(pri) calculates the mask for the individual priority pri. The function LOG_UPTO(pri) calculates the mask for all priorities up to and including pri.

The module defines the following constants:

Priority levels (high to low):

LOG_EMERG, LOG_ALERT, LOG_CRIT, LOG_ERR, LOG_WARNING, LOG_NOTICE, LOG_INFO, LOG_DEBUG.

Facilities:

LOG_KERN, LOG_USER, LOG_MAIL, LOG_DAEMON, LOG_AUTH, LOG_LPR, LOG_NEWS, LOG_UUCP, LOG_CRON and LOG_LOCAL0 to LOG_LOCAL7.

Log options:

LOG_PID, LOG_CONS, LOG_NDELAY, LOG_NOWAIT and LOG_PERROR if defined in <syslog.h>.

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