:mod:`syslog` --- Unix syslog library routines ============================================== .. module:: syslog :platform: Unix :synopsis: An interface to the Unix syslog library routines. 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. This module wraps the system ``syslog`` family of routines. A pure Python library that can speak to a syslog server is available in the :mod:`logging.handlers` module as :class:`SysLogHandler`. The module defines the following functions: .. function:: 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 :const:`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 :func:`openlog` call is used. If :func:`openlog` has not been called prior to the call to :func:`syslog`, ``openlog()`` will be called with no arguments. .. function:: openlog([ident[, logoption[, facility]]]) Logging options of subsequent :func:`syslog` calls can be set by calling :func:`openlog`. :func:`syslog` will call :func:`openlog` with no arguments if the log is not currently open. The optional *ident* keyword argument is a string which is prepended to every message, and defaults to ``sys.argv[0]`` with leading path components stripped. The optional *logoption* keyword argument (default is 0) is a bit field -- see below for possible values to combine. The optional *facility* keyword argument (default is :const:`LOG_USER`) sets the default facility for messages which do not have a facility explicitly encoded. .. function:: closelog() Reset the syslog module values and call the system library ``closelog()``. This causes the module to behave as it does when initially imported. For example, :func:`openlog` will be called on the first :func:`syslog` call (if :func:`openlog` hasn't already been called), and *ident* and other :func:`openlog` parameters are reset to defaults. .. function:: setlogmask(maskpri) Set the priority mask to *maskpri* and return the previous mask value. Calls to :func:`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): :const:`LOG_EMERG`, :const:`LOG_ALERT`, :const:`LOG_CRIT`, :const:`LOG_ERR`, :const:`LOG_WARNING`, :const:`LOG_NOTICE`, :const:`LOG_INFO`, :const:`LOG_DEBUG`. Facilities: :const:`LOG_KERN`, :const:`LOG_USER`, :const:`LOG_MAIL`, :const:`LOG_DAEMON`, :const:`LOG_AUTH`, :const:`LOG_LPR`, :const:`LOG_NEWS`, :const:`LOG_UUCP`, :const:`LOG_CRON`, :const:`LOG_SYSLOG` and :const:`LOG_LOCAL0` to :const:`LOG_LOCAL7`. Log options: :const:`LOG_PID`, :const:`LOG_CONS`, :const:`LOG_NDELAY`, :const:`LOG_NOWAIT` and :const:`LOG_PERROR` if defined in ````. Examples -------- Simple example ~~~~~~~~~~~~~~ A simple set of examples:: import syslog syslog.syslog('Processing started') if error: syslog.syslog(syslog.LOG_ERR, 'Processing started') An example of setting some log options, these would include the process ID in logged messages, and write the messages to the destination facility used for mail logging:: syslog.openlog(logoption=syslog.LOG_PID, facility=syslog.LOG_MAIL) syslog.syslog('E-mail processing initiated...')