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NAME

Parse::Syslog - Parse Unix syslog files

SYNOPSIS

my $parser = Parse::Syslog->new( '/var/log/syslog', year => 2001);
while(my $sl = $parser->next) {
    ... access $sl->{timestamp|host|program|pid|text} ...
}

DESCRIPTION

Unix syslogs are convenient to read for humans but because of small differences between operating systems and things like 'last message repeated xx times' not very easy to parse by a script.

Parse::Syslog presents a simple interface to parse syslog files: you create a parser on a file (with new) and call next to get one line at a time with Unix-timestamp, host, program, pid and text returned in a hash-reference.

Constructing a Parser

new requires as first argument a source from where to get the syslog lines. It can be:

  • a file-name for the syslog-file to be parsed.

  • an IO::Handle object.

  • a File::Tail object as first argument, in which case the read method will be called to get lines to process.

After the file-name (or File::Tail object), you can specify options as a hash. The following options are defined:

type

Format of the "syslog" file. Can be one of:

syslog

Traditional "syslog" (default)

metalog

Metalog (see http://metalog.sourceforge.net/)

year

Syslog files usually do store the time of the event without year. With this option you can specify the start-year of this log. If not specified, it will be set to the current year.

GMT

If this option is set, the time in the syslog will be converted assuming it is GMT time instead of local time.

repeat

Parse::Syslog will by default repeat xx times events that are followed by messages like 'last message repeated xx times'. If you set this option to false, it won't do that.

arrayref

If this option is true, next will return an array-ref instead of a hash-ref (and is thus a bit faster), with the following contents:

0:

timestamp

1:

host

2:

program

3:

pid

4:

text

locale

Optional. Specifies an additional locale name or the array of locale names for the parsing of log files with national characters.

allow_future

If true will allow for timestamps in the future. Otherwise timestamps of one day in the future and more will not be returned (as a safety measure against wrong configurations, bogus --year arguments, etc.)

Parsing the file

The file is parse one line at a time by calling the next method, which returns a hash-reference containing the following keys:

timestamp

Unix timestamp for the event.

host

Host-name where the event did happen.

program

Program-name of the program that generated the event.

pid

PID of the Program that generated the event. This information is not always available for every operating system.

text

Text description of the event.

msgid

Message numeric identifier, available only on Solaris >= 8 with "message ID generation" enabled".

facility

Log facility name, available only on Solaris >= 8 with "message ID generation" enabled".

level

Log level, available only on Solaris >= 8 with "message ID generation" enabled".

BUGS

There are many small differences in the syslog syntax between operating systems. This module has been tested for syslog files produced by the following operating systems:

Debian GNU/Linux 2.4 (sid)
Solaris 2.6
Solaris 8

Report problems for these and other operating systems to the author.

COPYRIGHT

Copyright (c) 2001, Swiss Federal Institute of Technology, Zurich. All Rights Reserved.

LICENSE

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

David Schweikert <dws@ee.ethz.ch>

HISTORY

2001-08-12 ds 0.01 first version
2001-08-19 ds 0.02 fix 'last message repeated xx times', Solaris 8 problems
2001-08-20 ds 0.03 implemented GMT option, year specification, File::Tail
2001-10-31 ds 0.04 faster time parsing, implemented 'arrayref' option, better time-increment algorithm
2002-01-29 ds 0.05 ignore -- MARK -- lines, low-case months, space in program names
2002-05-02 ds 1.00 HP-UX fixes, parse 'above message repeats xx times'
2002-05-25 ds 1.01 added support for localized month names (uchum@mail.ru)
2002-10-28 ds 1.02 fix off-by-one-hour error when running during daylight saving time switch
2004-01-19 ds 1.03 do not allow future dates (if allow_future is not true)
2004-07-11 ds 1.04 added support for type 'metalog'
2005-12-24 ds 1.05 allow passing of a IO::Handle object to new