Create Log4cpp Layout
Apart from the Simple and Basic Layout of log4cpp, you can create your own log pattern using the Pattern Layout. But you can add certain strings to the pattern. If you want to add additional functionality like displaying process ID, hostname using functions like getpid(), gethostbyname(), you need to create your own layout. You can [...]
How to direct logs to multiple log files (destinations) – log4cpp
log4cpp can not only be used to log the events to a log file or standard output, but also helps you to log events to multiple destinations. For this purpose, either you can add multiple appenders to a single category or make use of multiple Categories. We will explore the first options. With this option, [...]
log4cpp ConfigureFailure
log4cpp programs can be configured using configuration files. But while using log4cpp configurations, you may come across various errors. These can be tracked using log4cpp::ConfigureFailure. See the following program how the missing file error is caught. #include <stdio.h> #include <stdlib.h> #include <log4cpp/Category.hh> #include <log4cpp/PropertyConfigurator.hh> #include <log4cpp/Configurator.hh> using namespace std; int main() { /*Setting up Appender, [...]
log4cpp: Logging Events and Priorities
The most important aspect of a log message is its priority. Take a simple scenario, when you are debugging your program, you want to display all the logs in your program. At that moment, you are not concerned about the resource crunch and performance impact. But when your program is running, you do not want [...]
log4cpp Category
Every log message has a priority. But depending on the scenario we decide whether we need to log a message or not. Like every message has a priority, similarly every scenario has a priority. We have the following priorities arranged in the descending order. EMERG, FATAL ALERT CRIT ERROR WARN NOTICE INFO DEBUG NOTSET (no [...]
log4cpp::PropertyConfigurator – Configure with configuration files
log4cpp can also be configured with the configuration files. log4cpp::PropertyConfigurator can be used for this purpose. It has a single function which takes as input the configuration file. void configure (const std::string &initFileName) Simply specify the configuration in a file. You must specify the layout, priority and the appender in the configuration file as shown [...]
log4cpp::PatternLayout – Available log4cpp log formats
log4cpp supports three layouts: Simple Layout, Basic Layout and PatternLayout. Simple and Basic Layout are the simplest ones and you need not configure them in any way. The display the log in a fixed format. log4cpp::PatternLayout has the additional advantage that it supports four different formats and provides a mechanism to create a format of [...]