Overview

The Read File program is only a demonstration program.

Originally, the program was intended to faciltate testing a certain behavior of backup programs that are capable of mounting a virtual drive from a backup file.

In particular, the program demonstrates that it is possible to process certain files that fail to:

Be restored from a backup or ZIP program archive; or
Be included in a ZIP archive or a file based backup; or
Be defragmented.

As a side effect, the program can be used to demonstrate how long it takes to read a file, using various buffer sizes, and how the speed may vary depending on whether the file is on a physical or virtual drive.

Output

Other than the information displayed in the program's Form, the program creates no output.

Requirements

The program was compiled using Microsoft Visual Basic 6 (with SP 6).

In order to run this program, you will need to have the following installed:

Windows 2000, or later.
Either Microsoft Visual Basic 6 or the Microsoft Visual Basic 6 run-time files: If you have neither, then you can download the Visual Basic 6 run-time files by following the instructions in VBRun60.exe Installs Visual Basic 6.0 Run-Time Files.

Restrictions

I have developed the program using Microsoft Windows 2000, and intentionally designed the program so that it will not work on operating systems older than Microsoft Windows 2000.

Running the program

There is no installation necessary, just directly run the program by double-clicking on the ReadFile.exe file, or by using a shortcut to that file.

When you run the program, a Visual Basic 6 Form will be displayed that looks something like the Form below. The Form was designed using a screen resolution of 1280 x 1024.

The Form includes the following controls.

Control	Purpose
Attempt to bypass errors	Checking the Attempt to bypass errors box will cause the program to take additional measures to attempt to access files that may fail to be accessed using the usual techniques.
Use Unicode	Checking the Use Unicode box will cause the program to use a Unicode API to attempt to access files that may fail to be accessed using the usual non-Unicode API.
Buffer Size (bytes)	Choose one of the preset buffer sizes, or enter a size of your own choosing. The buffer is not freed until either the program ends or the Free buffer button is used.
Free buffer	Frees the memory allocated to the buffer.
Select File	Clicking on the Select File button will allow you to choose the file to be read.
ReadFile	After choosing a file with the Select File button, clicking on the ReadFile button will read the file.
Bye Bye!	Exit the program, even while a file is being read.