Mellinger at 13:57, 19 June 2008

2008-06-19T13:57:47Z

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==Location==
<tt>BCI2000/src/shared/utils</tt>

==Synopsis==
The <tt>LogFile</tt> class transparently handles output into a log file. The output log file is maintained in the current [[BCI2000_Glossary#Session|session directory]], and carries the session name, followed with a user-specified extension. The log file's contents are never overwritten; rather, new entries are appended to it.
Creating an instance of <tt>LogFile</tt> and writing to it is sufficient to create a log file at an appropriate location; no further programmer interaction is required.

The <tt>LogFile</tt> class inherits from <tt>std::ofstream</tt> and provides the full interface of STL <tt>ostreams</tt>, allowing to use convenient output notation as in
myLogFile << "Run number " << runNumber << " started." << endl;

==Methods==
===LogFile(string FileExtension=".log")===
When creating a <tt>LogFile</tt> object, specify the desired file extension as a string argument. Typically, the specified extension begins with a separating dot. By default, <tt>.log</tt> is chosen as a file extension.

==Remarks==
When writing a BCI2000 application module, it is recommended to use the [[Programming Reference:ApplicationBase Class|<tt>ApplicationBase</tt>]] class as a base class for the application's task filter. In this case, dealing with a <tt>LogFile</tt> object is not necessary; rather, the <tt>ApplicationBase</tt> class provides a <tt>LogFile</tt> object that is tied to a [[Programming Reference:GenericVisualization Class]] object such that output will be written to the screen and to a log file simultaneously. For details, refer to [[Programming Reference:ApplicationBase Class]].

==See also==
[[Programming Reference:ApplicationBase Class]], [[Programming Reference:Debug Output]], [[Programming Reference:Errors and Warnings]]

[[Category:Framework API]][[Category:Development]]

Programming Reference:LogFile Class - Revision history

Mellinger at 13:57, 19 June 2008