You can lock flat files using the DTWF_OPEN and DTWF_CLOSE functions. These functions allow you to reserve the file for the Net.Data process that needs to access the file so that no other processes can read or update the file.
To lock a file, use the DTWF_OPEN function. This function ensures the file is unavailable to other applications and prevents the file from changing between the time it is read and updated.
To free the file, use the DTWF_CLOSE function. This function releases the file from the Net.Data process's control and allows other processes to read or update the file.