In light of or more of the recent threads in this area, here's a little something from the "Advisor Tips" section of FPA. As a side note, I find it interesting that Steve Sawyer is no longer the editor of this column.

The title of this gem is "Determine if a Drive Exists". Without getting into any of the text, it has the following RETURN:

RETURN (DISKSPACE(tcDrive) > 0)

where tcDrive is the drive in question.

Only one problem...under NT you get a nasty error dialog if SetErrorMode() isn't properly called (and later restored to it's original state) to disable it.

Now if you're going to be mucking about with API anyway, then...

DECLARE INTEGER GetLogicalDrives IN Win32API
RETURN BITTEST(GetLogicalDrives(), ASC(UPPER(tcDrive)) - 65)

gets the job done very cleanly.

Back in the January, 2000 issue, while Steve was still the Contributing Editor, there was a tip that synchronized the VFP _DBLCLICK system variable with the setting the user had established in the Control Panel:

DECLARE INTEGER GetDoubleClickTime IN Win32API
_DBLCLICK = GetDoubleClickTime() / 1000