File Streams - Appending to File

I have a simple Logging function for a project, but I can't seem to get it to work correctly. Currently, the code just seems to overwrite a single line each time.

I am not sure if it's related to the closing and re-opening. (Incidentally, what diffeerence(s) are there between OpenFile and WriteFile? ) However, I don't like to leave any files Open, especially as my program may involve other read/writes to other files elsewhere.

Function Debug(sDebugFunction$="APPLICATION RUN",sDebugResult$="LOG START")

	If (DebugOn())
		DebugFile=WriteFile(fLOGFILE$)
		SeekFile(DebugFile,FileSize(fLOGFILE$))
		sLine$=CurrentDate$()+" | "+CurrentTime$()+" | "+sDebugFunction$+" | "+sDebugResult$
		WriteLine(DebugFile,sLine$)
		CloseFile DebugFile
	EndIf
        Return
End Function

Any help would be really appreciated.

Maybe try doing ReadLine to see if there is anything on that line first and loop it till it gets to an empty spot?

Use OpenFile(), As far as im aware WriteFile() zeros the file ready for writing. You might want to use WriteFile() first to create a file. OpenFile() requires that the file exists.

May offer some help:
http://www.blitzbasic.com/Community/posts.php?topic=27896

Yes, you need to check to see if the log file exists, if it does use OpenFile, else use WriteFile.

Oh the file definitely exists.

OpenFile worked fine. Thanks for the info. I shoulda tried that before posting, really ;)

file = OpenFile(path$)
SeekFile file, FileSize(path$)

The file is now opened for reading and writing and the file position is at the end of the file.