WriteFile and CGI

VB CGI executable is in \Test\. Why do I have to specify the full file path like this:

VB Code:

FILEOUT = CreateFile("C:\Inetpub\wwwroot\Test\image.log", GENERIC_WRITE, FILE_SHARE_READ, _
        ByVal 0&, OPEN_ALWAYS, FILE_ATTRIBUTE_ARCHIVE, 0)

Instead of a relative path like this?

VB Code:

FILEOUT = CreateFile(".\image.log", GENERIC_WRITE, FILE_SHARE_READ, _
        ByVal 0&, OPEN_ALWAYS, FILE_ATTRIBUTE_ARCHIVE, 0)
'Or this?
FILEOUT = CreateFile("image.log", GENERIC_WRITE, FILE_SHARE_READ, _
        ByVal 0&, OPEN_ALWAYS, FILE_ATTRIBUTE_ARCHIVE, 0)