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Log::Handler::Output::File.3pm

NAME

Log::Handler::Output::File - Log messages to a file.

SYNOPSIS

     use Log::Handler::Output::File;
 
     my $log = Log::Handler::Output::File->new(
         filename    => "file.log",
         filelock    => 1,
         fileopen    => 1,
         reopen      => 1,
         mode        => "append",
         autoflush   => 1,
         permissions => "0664",
         utf8        => 0,
     );
 
     $log->log(message => $message);
 
 

DESCRIPTION

Log messages to a file.

METHODS

new()

Call "new()" to create a new Log::Handler::Output::File object.

The following options are possible:

filename

With "filename" you can set a file name as a string or as a array reference. If you set a array reference then the parts will be concat with "catfile" from "File::Spec".

Set a file name:

     my $log = Log::Handler::Output::File->new( filename => "file.log"  );
 
 

Set a array reference:

     my $log = Log::Handler::Output::File->new(
 
         # foo/bar/baz.log
         filename => [ "foo", "bar", "baz.log" ],
 
         # /foo/bar/baz.log
         filename => [ "", "foo", "bar", "baz.log" ],
 
     );
 
 

filelock

Maybe it's desirable to lock the log file by each write operation because a lot of processes write at the same time to the log file. You can set the option "filelock" to 0 or 1.

     0 - no file lock
     1 - exclusive lock (LOCK_EX) and unlock (LOCK_UN) by each write operation (default)
 
 

fileopen

Open a log file transient or permanent.

     0 - open and close the logfile by each write operation
     1 - open the logfile if C<new()> called and try to reopen the
         file if C<reopen> is set to 1 and the inode of the file has changed (default)
 
 

reopen

This option works only if option "fileopen" is set to 1.

     0 - deactivated
     1 - try to reopen the log file if the inode changed (default)
 
 

How to use fileopen and reopen

Please note that it's better to set "reopen" and "fileopen" to 0 on Windows because Windows unfortunately haven't the faintest idea of inodes.

To write your code independent you should control it:

     my $os_is_win = $^O =~ /win/i ? 0 : 1;
 
     my $log = Log::Handler::Output::File->new(
        filename => "file.log",
        mode     => "append",
        fileopen => $os_is_win
     );
 
 

If you set "fileopen" to 0 then it implies that "reopen" has no importance.

mode

There are three possible modes to open a log file.

     append - O_WRONLY | O_APPEND | O_CREAT (default)
     excl   - O_WRONLY | O_EXCL   | O_CREAT
     trunc  - O_WRONLY | O_TRUNC  | O_CREAT
 
 

"append" would open the log file in any case and appends the messages at the end of the log file.

"excl" would fail by open the log file if the log file already exists.

"trunc" would truncate the complete log file if it exists. Please take care to use this option.

Take a look to the documentation of "sysopen()" to get more information.

autoflush

     0 - autoflush off
     1 - autoflush on (default)
 
 

permissions

The option "permissions" sets the permission of the file if it creates and must be set as a octal value. The permission need to be in octal and are modified by your process's current ``umask''.

That means that you have to use the unix style permissions such as "chmod". 0640 is the default permission for this option. That means that the owner got read and write permissions and users in the same group got only read permissions. All other users got no access.

Take a look to the documentation of "sysopen()" to get more information.

utf8

If this option is set to 1 then UTF-8 will be set with "binmode()" on the output filehandle.

log()

Call "log()" if you want to log messages to the log file.

Example:

     $log->log(message => "this message goes to the logfile");
 
 

flush()

Call "flush()" if you want to re-open the log file.

This is useful if you don't want to use option ``reopen''. As example if a rotate mechanism moves the logfile and you want to re-open a new one.

validate()

Validate a configuration.

reload()

Reload with a new configuration.

errstr()

Call "errstr()" to get the last error message.

close()

Call "close()" to close the log file yourself - normally you don't need to use it, because the log file will be opened and closed automatically.

PREREQUISITES

     Carp
     Fcntl
     File::Spec
     Params::Validate
 
 

EXPORTS

No exports.

REPORT BUGS

Please report all bugs to <jschulz.cpan(at)bloonix.de>.

If you send me a mail then add Log::Handler into the subject.

AUTHOR

Jonny Schulz <jschulz.cpan(at)bloonix.de>.

COPYRIGHT

Copyright (C) 2007-2009 by Jonny Schulz. All rights reserved.

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