/*!

\page mod_oflog oflog: a logging library based on log4cplus

This module contains classes which are used for logging purposes.  This library
is based on <a href="http://log4cplus.sourceforge.net/">log4cplus</a>.

The main classes are (in alphabetical order):
\li \b OFLog
\li \b OFLogger
\li \b dcmtk::log4cplus::ConsoleAppender
\li \b dcmtk::log4cplus::FileAppender
\li \b dcmtk::log4cplus::PatternLayout

\section Files

The following files provide sample configurations and further documentation:
\li \ref file_logger
\li \ref file_filelog

\section Examples

The following example shows how to use oflog in a console application.

\subsection actual_logging The actual logging

First we need the necessary headers and definitions:

\code
// Naturally, we need the header for oflog
#include "dcmtk/oflog/oflog.h"

// Then we create our logger object. The argument is the name of the logger
// which can be used to configure it from the config file
OFLogger my_log = OFLog::getLogger("dcmtk.apps.sample");
\endcode

That is all that is necessary to create log statements. You can now use any of
the following macros to generate log entries:

\code
OFLOG_FATAL(my_log, "This is a sample message of log level 'fatal'");
OFLOG_ERROR(my_log, "There are six log levels and each provides a OFLOG_level() macro");
OFLOG_WARN(my_log, "These macros are quite flexible");
OFLOG_INFO(my_log, "To output numbers like " << 5 << " you can use any iostream operations");
OFLOG_DEBUG(my_log, "Since iostreams are quite flexible themselves, a lot of stuff is possible");
OFLOG_TRACE(my_log, "hex numbers? 0x" << STD_NAMESPACE hex << 0x1234 << " and decimal numbers "
                 << STD_NAMESPACE dec << 0x1234 << " are no problem at all");
\endcode

\subsection configure_logging Configuring the logging

While the above code works by itself, the result is not nice and flexible. To
configure oflog with the help of OFCommandLine, you can do something like this:

\code
// This is just an example
cmd.addGroup("general options:", LONGCOL, SHORTCOL);
  // You own options here, e.g. --version
  cmd.addOption("--version", "print version information and exit", OFCommandLine::AF_Exclusive);
  // This call adds all of oflog's options, e.g. --debug and --quiet
  OFLog::addOptions(cmd);
\endcode

After you called OFConsoleApplication::parseCommandLine(), oflog can be set up
with one single call:

\code
OFLog::configureFromCommandLine(cmd, app);
\endcode

This is all that is necessary to configure the logger and have options like
<code>--verbose</code> and <code>--log-config</code> available.

Alternatively you can use OFLog::configure(), but this approach doesn't offer
the flexibility of <code>--log-level</code> and <code>--log-config</code>.

The default pattern for the log messages is "%P: %m%n", i.e. first character of
the log level (e.g. "D" for debug or "E" for error), a colon, the message and
a line break.

*/

/*!
    \page file_logger logger.cfg file
    \verbinclude ../etc/logger.cfg
*/
/*!
    \page file_filelog filelog.cfg file
    \verbinclude ../etc/filelog.cfg
*/