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Log-Handler-0.38_07
River stage two • 29 direct dependents • 41 total dependents
9 ++
/ Log::Handler::Output::File

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);

DESCRIPTION

Log messages to a file.

METHODS

new()

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

The new() method expected the options for the log file. Each option will be set to a default value if not set. If this method is called with no options then it creates an object to log to STDOUT with all default values.

log()

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

Example:

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

errstr()

This function returns the last error message.

OPTIONS

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. It's also possible to set a GLOBREF or a string as an alias for STDOUT or STDERR. The default is STDOUT for this option.

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' ]

    );

Set a GLOBREF

    open FH, '>', 'file.log' or die $!;
    my $log = Log::Handler::Output::File->new( filename => \*FH );

Or the same with

    open my $fh, '>', 'file.log' or die $!;
    my $log = Log::Handler::Output::File->new( filename => $fh );

Set STDOUT or STDERR

    my $log = Log::Handler::Output::File->new( filename => \*STDOUT );
    # or
    my $log = Log::Handler::Output::File->new( filename => \*STDERR );

If the option filename is set in a config file and you want to debug to your screen then you can set *STDOUT or *STDERR as a string.

    my $log = Log::Handler::Output::File->new( filename => '*STDOUT' );
    # or
    my $log = Log::Handler::Output::File->new( filename => '*STDERR' );

That is not possible:

    my $log = Log::Handler::Output::File->new( filename => '*FH' );

Note that if you set a GLOBREF to filename some options will be forced (overwritten) and you have to control the handles yourself. The forced options are

    fileopen => 1   # don't close
    filelock => 0   # don't lock
    reopen   => 0   # and don't reopen

The reason is simple: if you set *STDOUT as filename it would be very bad if it would be closed or locked.

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)

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
    excl   - O_WRONLY | O_EXCL   | O_CREAT (default)
    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. This is the default option because some security reasons.

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 informations.

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 informations.

utf8

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

PREREQUISITES

    Fcntl
    Params::Validate

EXPORTS

No exports.

REPORT BUGS

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

AUTHOR

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

QUESTIONS

Do you have any questions or ideas?

MAIL: <jschulz.cpan(at)bloonix.de>

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

COPYRIGHT

Copyright (C) 2007 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.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE SOFTWARE AS PERMITTED BY THE ABOVE LICENCE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE SOFTWARE (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE SOFTWARE TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.