agent::tag::caller(3)
NAME
Log::Agent::Tag::Caller - formats caller information
SYNOPSIS
Not intended to be used directly Inherits from Log::Agent::Tag.
DESCRIPTION
This class handles caller information for Log::Agent ser
vices and is not meant to be used directly.
This manpage therefore only documents the creation routine
parameters that can be specified at the Log::Agent level
via the "-caller" switch in the logconfig() routine.
CALLER INFORMATION ENTITIES
This class knows about four entities: package, filename,
line and subroutine, which are to be understood within the
context of the Log::Agent routine being called (e.g. a
logwarn() routine), namely:
- package
- This is the package name where the call to the log_
warn() routine was made. It can be specified as
"pack" for short, or spelled out completely. - filename
- This is the file where the call to the logwarn() rou
tine was made. It can be specified as "file" for
short, or spelled out completely. - line
- This is the line number where the call to the log_
warn() routine was made, in file filename. The name is short enough to be spelled out completely. - subroutine
- This is the subroutine where the call to the logwarn()
routine was made. If the call is made outside a sub
routine, this will be empty. The name is long enough
to warrant the "sub" abbreviation if you don't wish to
spell it out fully.
CREATION ROUTINE PARAMETERS
The purpose of those parameters is to define how caller
information entities (as defined by the previous section)
will be formatted within the log message.
- "-display" => string
- Specifies a string with minimal variable substitution:
only the caller information entities specified above,
or their abbreviation, will be interpolated. For
instance:
-display => '($package::$sub/$line)' - Don't forget to use simple quotes to avoid having Perl
interpolate those as variables, or escape their lead
ing "$" sign otherwise. Using this convention was
deemed to more readable (and natural in Perl) than
SGML entities such as "&pack;". - Using this switch supersedes the "-info" and "-format"
switches. - "-format" => printf format
- Formatting instructions for the caller information
entities listed by the "-info" switch. For instance:
-format => "%s:%4d" - if you have specified two entities in "-info".
- The special formatting macro %a stands for all the
entities specified by "-info" and is rendered by a
string where values are separated by ":". - "-info" => "space separated list of parameters"
- Specifies a list of caller information entities that
are to be formated using the "-format" specification.
For instance:
-info => "pack sub line" - would only report those three entites.
- "-postfix" => flag
- Whether the string resulting from the formatting of
the caller information entities should be appended to
the regular log message or not (i.e. prepended, which
is the default). - "-separator" => string
- The separation string between the tag and the log mes
sage. A single space by default.
AUTHORS
Raphael Manfredi <Raphael_Manfredi@pobox.com> created the
module, it is currently maintained by Mark Rogaski <mro
gaski@cpan.org>.
Thanks to Jeff Boes for uncovering wackiness in caller().
LICENSE
Copyright (C) 1999 Raphael Manfredi. Copyright (C) 2002
Mark Rogaski; all rights reserved.
See Log::Agent(3) or the README file included with the
distribution for license information.