NAME
Sys::Syslog - Perl interface to the UNIX syslog(3) calls
VERSION
Version 0.13
SYNOPSIS
use Sys::Syslog; # all except setlogsock(), or:
use Sys::Syslog qw(:DEFAULT setlogsock); # default set, plus setlogsock()
use Sys::Syslog qw(:standard :macros); # standard functions, plus macros
setlogsock $sock_type;
openlog $ident, $logopt, $facility; # don't forget this
syslog $priority, $format, @args;
$oldmask = setlogmask $mask_priority;
closelog;DESCRIPTION
Sys::Syslog is an interface to the UNIX syslog(3) program. Call syslog() with a string priority and a list of printf() args just like syslog(3).
EXPORTS
Sys::Syslog exports the following Exporter tags:
:standardexports the standardsyslog(3)functions:openlog closelog setlogmask syslog:extendedexports the Perl specific functions forsyslog(3):setlogsock:macrosexports the symbols corresponding to most of yoursyslog(3)macros. See "CONSTANTS" for the supported constants and their meaning.
By default, Sys::Syslog exports the symbols from the :standard tag.
FUNCTIONS
- openlog($ident, $logopt, $facility)
-
Opens the syslog.
$identis prepended to every message.$logoptcontains zero or more of the wordspid,ndelay,nowait. Theconsoption is ignored, since the failover mechanism will drop down to the console automatically if all other media fail.$facilityspecifies the part of the system to report about, for exampleLOG_USERorLOG_LOCAL0: see yoursyslog(3)documentation for the facilities available in your system. Facility can be given as a string or a numeric macro.This function will croak if it can't connect to the syslog daemon.
Note that
openlog()now takes three arguments, just likeopenlog(3).You should use openlog() before calling syslog().
Options
ndelay- Open the connection immediately (normally, the connection is opened when the first message is logged).nowait- Don't wait for child processes that may have been created while logging the message. (The GNU C library does not create a child process, so this option has no effect on Linux.)pid- Include PID with each message.
Examples
Open the syslog with options
ndelayandpid, and with facilityLOCAL0:openlog($name, "ndelay,pid", "local0");Same thing, but this time using the macro corresponding to
LOCAL0:openlog($name, "ndelay,pid", LOG_LOCAL0); - syslog($priority, $message)
- syslog($priority, $format, @args)
-
If
$prioritypermits, logs$messageorsprintf($format, @args)with the addition that%min $message or$formatis replaced with"$!"(the latest error message).$prioritycan specify a level, or a level and a facility. Levels and facilities can be given as strings or as macros.If you didn't use
openlog()before usingsyslog(),syslog()will try to guess the$identby extracting the shortest prefix of$formatthat ends in a":".Examples
syslog("info", $message); # informational level syslog(LOG_INFO, $message); # informational level syslog("info|local0", $message); # information level, Local0 facility syslog(LOG_INFO|LOG_LOCAL0, $message); # information level, Local0 facility- Note
-
Sys::Syslogversion v0.07 and older passed the$messageas the formatting string tosprintf()even when no formatting arguments were provided. If the code callingsyslog()might execute with older versions of this module, make sure to call the function assyslog($priority, "%s", $message)instead ofsyslog($priority, $message). This protects against hostile formatting sequences that might show up if $message contains tainted data.
- setlogmask($mask_priority)
-
Sets the log mask for the current process to
$mask_priorityand returns the old mask. If the mask argument is 0, the current log mask is not modified. See "Levels" for the list of available levels.Examples
Only log errors:
setlogmask(LOG_ERR);Log critical messages, errors and warnings:
setlogmask(LOG_CRIT|LOG_ERR|LOG_WARNING); - setlogsock($sock_type)
- setlogsock($sock_type, $stream_location) (added in 5.004_02)
-
Sets the socket type to be used for the next call to
openlog()orsyslog()and returns true on success,undefon failure.A value of
"unix"will connect to the UNIX domain socket (in some systems a character special device) returned by the_PATH_LOGmacro (if your system defines it), or /dev/log or /dev/conslog, whatever is writable. A value of 'stream' will connect to the stream indicated by the pathname provided as the optional second parameter. (For example Solaris and IRIX require"stream"instead of"unix".) A value of"inet"will connect to an INET socket (eithertcporudp, tried in that order) returned bygetservbyname()."tcp"and"udp"can also be given as values. The value"console"will send messages directly to the console, as for the"cons"option in the logopts inopenlog().A reference to an array can also be passed as the first parameter. When this calling method is used, the array should contain a list of sock_types which are attempted in order.
The default is to try
tcp,udp,unix,stream,console.Giving an invalid value for
$sock_typewill croak. - closelog()
-
Closes the log file and return true on success.
EXAMPLES
openlog($program, 'cons,pid', 'user');
syslog('info', '%s', 'this is another test');
syslog('mail|warning', 'this is a better test: %d', time);
closelog();
syslog('debug', 'this is the last test');
setlogsock('unix');
openlog("$program $$", 'ndelay', 'user');
syslog('notice', 'fooprogram: this is really done');
setlogsock('inet');
$! = 55;
syslog('info', 'problem was %m'); # %m == $! in syslog(3)
# Log to UDP port on $remotehost instead of logging locally
setlogsock('udp');
$Sys::Syslog::host = $remotehost;
openlog($program, 'ndelay', 'user');
syslog('info', 'something happened over here');CONSTANTS
Facilities
LOG_AUTH- security/authorization messagesLOG_AUTHPRIV- security/authorization messages (private)LOG_CRON- clock daemon (cron and at)LOG_DAEMON- system daemons without separate facility valueLOG_FTP- ftp daemonLOG_KERN- kernel messagesLOG_LOCAL0throughLOG_LOCAL7- reserved for local useLOG_LPR- line printer subsystemLOG_MAIL- mail subsystemLOG_NEWS- USENET news subsystemLOG_SYSLOG- messages generated internally by syslogdLOG_USER(default) - generic user-level messagesLOG_UUCP- UUCP subsystem
Levels
LOG_EMERG- system is unusableLOG_ALERT- action must be taken immediatelyLOG_CRIT- critical conditionsLOG_ERR- error conditionsLOG_WARNING- warning conditionsLOG_NOTICE- normal, but significant, conditionLOG_INFO- informational messageLOG_DEBUG- debug-level message
DIAGNOSTICS
- Invalid argument passed to setlogsock
-
(F) You gave
setlogsock()an invalid value for$sock_type. - no connection to syslog available
-
(F)
syslog()failed to connect to the specified socket. - stream passed to setlogsock, but %s is not writable
-
(W) You asked
setlogsock()to use a stream socket, but the given path is not writable. - stream passed to setlogsock, but could not find any device
-
(W) You asked
setlogsock()to use a stream socket, but didn't provide a path, andSys::Syslogwas unable to find an appropriate one. -
(W) You asked
setlogsock()to use a TCP socket, but the service is not available on the system. - syslog: expecting argument %s
-
(F) You forgot to give
syslog()the indicated argument. - syslog: invalid level/facility: %s
-
(F) You specified an invalid level or facility, like
LOG_KERN(which is reserved to the kernel). - syslog: too many levels given: %s
-
(F) You specified too many levels.
- syslog: too many facilities given: %s
-
(F) You specified too many facilities.
- syslog: level must be given
-
(F) You forgot to specify a level.
-
(W) You asked
setlogsock()to use a UDP socket, but the service is not available on the system. - unix passed to setlogsock, but path not available
-
(W) You asked
setlogsock()to use a UNIX socket, butSys::Syslogwas unable to find an appropriate an appropriate device.
SEE ALSO
Syslogging with Perl, http://lexington.pm.org/meetings/022001.html
AUTHOR
Tom Christiansen <tchrist@perl.com> and Larry Wall <larry@wall.org>.
UNIX domain sockets added by Sean Robinson <robinson_s@sc.maricopa.edu> with support from Tim Bunce <Tim.Bunce@ig.co.uk> and the perl5-porters mailing list.
Dependency on syslog.ph replaced with XS code by Tom Hughes <tom@compton.nu>.
Code for constant()s regenerated by Nicholas Clark <nick@ccl4.org>.
Failover to different communication modes by Nick Williams <Nick.Williams@morganstanley.com>.
Extracted from core distribution for publishing on the CPAN by Sébastien Aperghis-Tramoni <sebastien@aperghis.net>.
BUGS
Please report any bugs or feature requests to bug-sys-syslog at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Sys-Syslog. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.
SUPPORT
You can find documentation for this module with the perldoc command.
perldoc Sys::SyslogYou can also look for information at:
AnnoCPAN: Annotated CPAN documentation
CPAN Ratings
RT: CPAN's request tracker
Search CPAN
LICENSE
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.