FoxPro FILE() with NUL to check directory does not work

[ednt]

Hi,

I need to check if a directory exists.

This can be done by

? FILE('C:\TMP\NUL')

But it does not work.

According to the documentation it should work from DOS 3.0

learn.microsoft.com/en-us/previous-versions/troubleshoot/visualstudio/foxpro/check-for-existence-of-directory

With ADIR() and ASCAN() I can build a workaround, but this takes more time for the check.

I use vDos 2022.05.01

Any idea why FILE() fails?

Bernd

[Jos]

Ralf Brown's Interrupt List (http://www.ctyme.com/intr/rb-2977.htm) states:

Notes: For search attributes other than 08h, all files with at MOST the specified combination of hidden, system, and directory attributes will be returned.

Although [path\]NUL is at first eventually regarded ‘found’, it’s then dropped if the device attribute (40h) was not included in the search attributes.
The device attribute is however essentially non-existent in file searches. For the next vDos version I changed the test to only attribute 08h (volume) being set.
FoxPro FILE() sets the search attributes to 0.

Jos