I need to generate a unique temporary file with a .csv extension.
What I do right now is
string filename = System.IO.Path.GetTempFileName().Replace(
The MSDN documentation for C++'s GetTempFileName discusses your concern and answers it:
GetTempFileName is not able to guarantee that the file name is unique.
Only the lower 16 bits of the uUnique parameter are used. This limits GetTempFileName to a maximum of 65,535 unique file names if the lpPathName and lpPrefixString parameters remain the same.
Due to the algorithm used to generate file names, GetTempFileName can perform poorly when creating a large number of files with the same prefix. In such cases, it is recommended that you construct unique file names based on GUIDs.