DIRTY.COM (DIRectory utiliTY) ----------------------------- This program enables users to perform advanced directory maintenance and will also retrieve hidden "SYSTEM FILES"! RUNNING DIRTY ------------- When the program is run you are asked to select an option from a list of seven. Option 1. ---------- Global erase. This will erase all current unerased files on the selected drive. ALL the files are erased. e.g. locked and system files have no protection but as you will see from the next option this doesn't matter at all. Option 2. --------- Global unerase. This will unerase all erased files on the selected drive, all files are retrieved even ones you thought you had lost ages ago! You may find that certain file names appear more than once, this is correct as the program looks at each extent in the directory. Each extent is worth 16K (a one byte program will have its own extent) so if you have a program that is between 16K and 32K long you will see the program name appear twice. This is handy as a check against file corruption. For example, If you knew you had erased a program that was over 16K (e.g. 22K) long and at some later date you decide to retrieve it, you will expect to see the file name twice in the unerased file list, If there is only one then DOS has allocated one of your erased extents to something else and the program will be useless. This information is not available once the file has been erased. So, it is impossible to say how long a program was, unless the last extent is still on the disc. (improbable!) Then by examining the allocation blocks assigned to the extent some idea of the original file size may be obtained. Once a file has been erased, DOS re-assigns the old files allocation blocks. The point being, Although it may appear that you have been able to retrieve an old file, it doesn't necessarily follow that the information contained within that file is the original information. If your knowledge of the DOS is limited and you didn't follow the last part, don't worry. If a program is over 16K long, DOS hides the second entry from you. DIRTY will show you the correct number of entries if the program has more than one extent, When DOS erases a file it erases all entries so as to make all the extents available to other data, if you then wish to enable an erased file with more than one extent you must unerase all entries as they appear or when DOS comes to load the program, some of the program will be missing. The opposite is of course true, therefore to erase a file properly. erase all entries (extents) from the directory. You may find you retrieve files that crash as you run them, this is because you are enabling an incomplete file. Always remember that an erased file is fair game to the disc operating system. All files are guaranteed preserved unless disc write operations take place or have taken place and an erased extent is allocated elsewhere. Option 3. --------- Selective erase. This allows you to erase files selectively. Each file name on the designated drive will appear with the question "Erase Y or N" beside it. As you answer either Y or N the next file name found on the disc is displayed for similar treatment. Option 4. ---------- Selective unerase. This is the same as option 3, but in reverse. Both options list and act upon locked and system files. Option 4. shows you when a locked or system file is brought back to the directory, DIRTY also unlocks the file. Again remember that is unimportant whether or not a file is/was locked, if you erase one by accident simply unerase it! Option 5. --------- DIR system files. This one is a bit sneaky as it lists the system files (erased or not) on the logged drive. To retrieve a system file simply unerase it with option 4, or if the file isn't erased simply erase it first using option 3. For example, you suspect a disc contains a system file, first run 'DIRTY', select option 5, this will list all the system files on disc, it will also say if the file is erased or not (yes some people do hide system files by erasing them!). Lets presume that the file isn't erased, note the file name, return to the main menu and select option 3. When you see your file name, erase it. Now select option 4 and unerase it. It will now be unlocked, in the directory and all yours! Alternatively you could have done a global erase/unerase, this will have the same effect on the system file, but of course, will unerase everything else it finds. Doing it the latter way will also show any newly enabled system files as they are unerased. Option 6. --------- DIR erased files. This will list all the erased files on the selected drive but will take no action upon them. The total number of files found during any operation is shown at the end of that operation as a hex figure. This is useful for finding out how much room is taken up by erased files, unerased files, system files etc.... The program is fully error trapped, this means that if say, the FDC (floppy disc controller) detects a fault, nothing is lost and the program and any trapped data may be recovered. As as example try taking your disc out and selecting an option from the menu... Option 7. --------- Pressing 'X' will terminate the program and pass control back to the operating system. NOTE ---- 1: DIRTY refers to files and extents as files. 2: ALWAYS exit the program by the exit option in the menu, or permanent damage may be done to your disc data.