Log4mql is a mql4 (MetaQuotes MetaTrader 4 Language) library for flexible logging to files and the terminal console. It is modeled after the Log4j Java library.

CLog4mql::getInstance().error(__FILE__, __LINE__, "Something unexpected happen");

  or (for more frequent usage)

CLog4mql* logger = CLog4mql::getInstance();
logger.error(__FILE__, __LINE__, "Something unexpected happen");
logger.info(__FILE__, __LINE__, "Calcumation done");
logger.debug(__FILE__, __LINE__, StringFormat("The result of %s is %d", string1, value1));

Dont forget at the end of your EA / Indicator / Script:

CLog4mql::release();

  or

logger.release();

The directory for the log4mql.conf and the log4mql.log files

• Normal mode: <mt4-data-dir>/MQL4/Files/
• Test mode: <mt4-data-dir>/tester/files/

You can configure the required log level for output in the configfile for each appending file and / or a global default.

• TRACE
• DEBUG
• INFO
• WARN
• ERROR
• CRIT