Depending on the priority of the log, the line starts with a string that indicates the type of log. For Example, Info logs start with [I], Warn logs start with [W], Fatal logs start with [F], and so on. This can be used to filter out the desired logs, for example, to filter out all the fatal logs from the log file log.log, use (under windows, cygwin or GNU Win32 grep can be used.):
The function entry and function exit logs have a open brace { and a close brace }. This is very helpful when the log is viewed in a editor which supports parantheses matching (ex: vim, kate)