1:mod:`syslog` --- Unix syslog library routines 2============================================== 3 4.. module:: syslog 5 :platform: Unix 6 :synopsis: An interface to the Unix syslog library routines. 7 8 9This module provides an interface to the Unix ``syslog`` library routines. 10Refer to the Unix manual pages for a detailed description of the ``syslog`` 11facility. 12 13This module wraps the system ``syslog`` family of routines. A pure Python 14library that can speak to a syslog server is available in the 15:mod:`logging.handlers` module as :class:`SysLogHandler`. 16 17The module defines the following functions: 18 19 20.. function:: syslog(message) 21 syslog(priority, message) 22 23 Send the string *message* to the system logger. A trailing newline is added 24 if necessary. Each message is tagged with a priority composed of a 25 *facility* and a *level*. The optional *priority* argument, which defaults 26 to :const:`LOG_INFO`, determines the message priority. If the facility is 27 not encoded in *priority* using logical-or (``LOG_INFO | LOG_USER``), the 28 value given in the :func:`openlog` call is used. 29 30 If :func:`openlog` has not been called prior to the call to :func:`syslog`, 31 ``openlog()`` will be called with no arguments. 32 33 34.. function:: openlog([ident[, logoption[, facility]]]) 35 36 Logging options of subsequent :func:`syslog` calls can be set by calling 37 :func:`openlog`. :func:`syslog` will call :func:`openlog` with no arguments 38 if the log is not currently open. 39 40 The optional *ident* keyword argument is a string which is prepended to every 41 message, and defaults to ``sys.argv[0]`` with leading path components 42 stripped. The optional *logoption* keyword argument (default is 0) is a bit 43 field -- see below for possible values to combine. The optional *facility* 44 keyword argument (default is :const:`LOG_USER`) sets the default facility for 45 messages which do not have a facility explicitly encoded. 46 47 48.. function:: closelog() 49 50 Reset the syslog module values and call the system library ``closelog()``. 51 52 This causes the module to behave as it does when initially imported. For 53 example, :func:`openlog` will be called on the first :func:`syslog` call (if 54 :func:`openlog` hasn't already been called), and *ident* and other 55 :func:`openlog` parameters are reset to defaults. 56 57 58.. function:: setlogmask(maskpri) 59 60 Set the priority mask to *maskpri* and return the previous mask value. Calls 61 to :func:`syslog` with a priority level not set in *maskpri* are ignored. 62 The default is to log all priorities. The function ``LOG_MASK(pri)`` 63 calculates the mask for the individual priority *pri*. The function 64 ``LOG_UPTO(pri)`` calculates the mask for all priorities up to and including 65 *pri*. 66 67The module defines the following constants: 68 69Priority levels (high to low): 70 :const:`LOG_EMERG`, :const:`LOG_ALERT`, :const:`LOG_CRIT`, :const:`LOG_ERR`, 71 :const:`LOG_WARNING`, :const:`LOG_NOTICE`, :const:`LOG_INFO`, 72 :const:`LOG_DEBUG`. 73 74Facilities: 75 :const:`LOG_KERN`, :const:`LOG_USER`, :const:`LOG_MAIL`, :const:`LOG_DAEMON`, 76 :const:`LOG_AUTH`, :const:`LOG_LPR`, :const:`LOG_NEWS`, :const:`LOG_UUCP`, 77 :const:`LOG_CRON`, :const:`LOG_SYSLOG` and :const:`LOG_LOCAL0` to 78 :const:`LOG_LOCAL7`. 79 80Log options: 81 :const:`LOG_PID`, :const:`LOG_CONS`, :const:`LOG_NDELAY`, :const:`LOG_NOWAIT` 82 and :const:`LOG_PERROR` if defined in ``<syslog.h>``. 83 84 85Examples 86-------- 87 88Simple example 89~~~~~~~~~~~~~~ 90 91A simple set of examples:: 92 93 import syslog 94 95 syslog.syslog('Processing started') 96 if error: 97 syslog.syslog(syslog.LOG_ERR, 'Processing started') 98 99An example of setting some log options, these would include the process ID in 100logged messages, and write the messages to the destination facility used for 101mail logging:: 102 103 syslog.openlog(logoption=syslog.LOG_PID, facility=syslog.LOG_MAIL) 104 syslog.syslog('E-mail processing initiated...') 105