This module provides an interface to the Unix
syslog library routines.
Refer to the Unix manual pages for a detailed description of the
This module wraps the system
syslog family of routines. A pure Python
library that can speak to a syslog server is available in the
logging.handlers module as
The module defines the following functions:
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[, logoption[, facility]]])¶
The optional ident keyword argument is a string which is prepended to every message, and defaults to
sys.argvwith 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
LOG_USER) sets the default facility for messages which do not have a facility explicitly encoded.
Changed in version 3.2: In previous versions, keyword arguments were not allowed, and ident was required. The default for ident was dependent on the system libraries, and often was
pythoninstead of the name of the Python program file.
Reset the syslog module values and call the system library
This causes the module to behave as it does when initially imported. For example,
openlog()will be called on the first
openlog()hasn’t already been called), and ident and other
openlog()parameters are reset to defaults.
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_LOCAL7, and, if defined in
- Log options:
LOG_NDELAY, and, if defined in
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...')