Unexpectedly I realized that plain


Dim lcDataText As New System.IO.StreamReader(“path\text_file.txt”)


opens file exclusively preventing access to this file from another independent application.

Another independent application (VFP9) uses code like:

rst_DTW = CreateObject("ADODB.Recordset")
rst_DTW.Open("select * from " + lcfile , cnnText, adOpenStatic, adLockReadOnly)


And if this (another) process opens the file first then the first process can also work with the file.


So far I tried to follow several examples, but with no luck.

1. Setting file attributes to READONLY.

2.
Dim lcDataText As System.IO.StreamReader = System.IO.File.OpenText(lcfilename)



3. Dim fs1 As System.IO.FileStream = New System.IO.FileStream(lcfilename, System.IO.FileMode.Open, System.IO.FileAccess.Read, System.IO.FileShare.Read)
Dim lcDataText As New System.IO.StreamReader(fs1)

Here in #3 when adding System.IO.FileShare.Read a note message pops up saying
“… However, even if this flag is specified, additional permissions might still be needed to access the file.” Probably I am falling under this “additional permissions” category, but what are they, and how to set them properly?

In addition, in another separate application I can use the following with no problem:
CREATE CURSOR yy (lcrec c(200))
Append from (lcfile) sdf

Looks like it is an evidence that something should be set for ADO recordset or connection.

Any recommendations are welcome.


Thanks