Curious... Windows Explorer doesn't let you create a file nor directory using a name starting with a period. However, you can still create one through the command line. From my guess, it may be connected to assumptions in connection to the "hide extensions for known file types" setting (i.e. the period is assumed to be a file extension separator). As for why GETDIR() doesn't list it... Maybe there is something regarding the underlying API calls being used? I have also encountered various annoyances and shortcomings of GETDIR() that I'm looking into a replacement. I believe there's a replacement for GETDIR() somewhere in the download area.

On a partially unrelated situation, under UNIX, files and directories starting with a period are hidden. You need to add the "-a" or "-A" option with the "ls" command to list them.