NAME

JLog::Writer - Perl extension for writing to a jlog journal.

SUMMARY

  use JLog::Writer;
  use Fcntl qw/:DEFAULT/;
  
  my $sub = "testsubscriber";
  my $log = "foo.jlog";
  
  # open a log - this respects stander Fcntl flags
  my $w = JLog::Writer->new($log, O_CREAT);
  
  # add a subscriber - without this there is danger that
  # a log may be expired without the unnamed subscriber
  # stating its intention to read.
  $w->add_subscriber($sub);
  
  # open for writing
  $w->open;
  
  foreach (1 ... 3) {
    # write to the queue
    $w->write("foo $_");
  }
  # close the queue
  $w->close;

DESCRIPTION

JLog::Writer allows you to access a jlog queue for writing.

INTERFACE

Constructor

new

  $w = JLog::Writer->new( $path_to_jlog, [ $flags [, $size ] ] );

Instantiates a JLog writer object associated with the JLog directory.

$path_to_jlog: The directory for the JLog queue.
$flags: Optional flags, from 'Fcntl'. The default is O_CREAT.
$size: Optional size of the individual journal files.

Subscriber Management

These functions are inherited from JLog

add_subscriber

  $w->add_subscriber( $name, [ $flag ] );

Add a subscriber to the JLog queue.

$name: The name of the subscriber.
$flag: An optional flag dictating where the subscriber should be marked interested from. The default is JLog::JLOG_BEGIN. The other available option is JLog::JLOG_END.

remove_subscriber

  $w->remove_subscriber ( $name );

Remove a subscriber to the JLog queue.

$name: The name of the subscriber.

Writing to the Queue

open

  $w->open();

Opens the JLog for writing.

write

  $w->write( $message [, $ts ] );

Write a message to the JLog.

$message: The message to write.
$ts: The timestamp (in epoch seconds) to set the record timestamp to. The default is time().

Internals

alter_journal_size

  $w->alter_journal_size( $size );

Set the size of the individual journal files.

$size: The desired size in bytes.

raw_size

  $size = $w->raw_size;

The size of the existing journal (including checkpointed but unpurged messages in the current journal file), in bytes.