It looks like you pass it a file name and it returns the full current path plus the file name. So SYS(2027,'test.txt') will return 'c:\vfp\test.txt' assuming that the current directory is c:\vfp. It doesn't seem that useful because you could just use SET('DEFAULT')+SYS(2003)+'test.txt' and get the same thing. Maybe there's some additional functionality there that I don't see. Also, it works in VFP 6.0, but it's still not documented in the VFP 6.0 help.

In general, I wouldn't use any undocumented functions, especially if there's a pretty easy alternative. You never know if it might disappear in a future version.

>Hi Everybody!
>
>I found an undocumented Sys() function in utility.vcx.(filelib class)
>Does somebody know, what it does?
>
>TIA
>
>BB