5.1.2.1 Logging hooks

Most diagnostic messages displayed by radiusd describe some events that occured while processig a certain incoming request. By default they contain only a short summary of the event. Logging hooks are means of controlling actual amount of information displayed in such messages. They allow you to add to the message being displayed any relevant information from the incoming request that caused the message to appear.

A hook is a special Rewrite function that takes three arguments and returns a string. There are two kinds of logging hooks: prefix and suffix. Return value from the prefix hook function will be displayed before the actual log message, that of the suffix hook function will be displayed after the message.

Furthermore, there may be global and channel-specific hooks. Global hooks apply to all categories, unless overridden by category-specific hooks. Global prefix hook is enabled by prefix-hook statement appearing in the logging block. Global suffix hook is enabled by suffix-hook statement. Both statements take as their argument the name of corresponding Rewrite function.

For detailed information about writing logging hooks, See section 11.2.7 Logging Hook Functions.