Is there any way to decode a PICS Rules File?
Contains settings and preferences used by the Windows operating system.
The file is given by:
Q:F]9y3n5|dp:n4hU)qbs;!&-bzh
The PICSRules spec defines what PICS rules should look like. I don't think your file is one of those.
Is that the entire file contents above?
Are you sure that it's definitely a PICS rules file? There are many file types which use the .prf extension, perhaps it's one of those.
Related
When writing to a binary file, when should I use .bin vs .dat? If I'm just trying to store information not meant to be read by humans, like item description/serial number pair, does it matter which one I pick if I'm just trying to make it unreadable from a text editor?
Let me give you some brief details about these files :
.BIN File : The BIN file type is primarily associated with 'Binary File'. Binary files are used for a wide variety of content and can be associated with a great many different programs. In general, a .BIN file will look like garbage when viewed in a file editor.
.DAT File : The DAT file type is primarily associated with 'Data'. Can be just about anything: text, graphic, or general binary data. Data file in special format or ASCII.
Reference:
Abhijit Banerjee answered that question on quora
.dat is a more frequently used suffix for binary data. It doesn't matter what extension you pick, as long as you are on Unix or Linux based systems.
Sufixes can mean whatever you want them to mean... Those rules are more like guidelines than actual rules...
However, BIN seems like a short to binary, so a BIN file will likely hold data in binary form. DAT seems like a short to data, so a DAT file will contain information in whatever format the developer of the program that reads that file seems fit (ASCII, Binary, a mix of them, something else entirely)
On a UNIX system, there is no difference. The extensions are interchangeable.
If you do not put any extension, it makes it kinda hard for someone not knowing what the file's extension should be, to open the file. Additionally, with Unix or Linux, if you place a dot (period) before the file name, the file hides itself.
As a general question: What's the role of file extension when determining file types?
For example, I can change .jpeg file to .png extension and even .txt. Of course, in the case of changing to .txt, it will neither be opened as picture, nor readable.
To determine file type, it seems the safe way is to parse the first few bytes of the file. If extension is not trustable, extension is no more than file name.
As a general rule, you should ALWAYS parse the COMPLETE file in order to be sure that the file is what the extension says. As you can easily imagine, it is pretty simple to create a binary file resembling a e.g. BMP (with a correct header) but then containing something different.
You should never trust the extension neither the header because otherwise a malicious user could exploit some of your code to generate e.g. a buffer overflow, and this is absolutely paramount if you are writing programs that must run at root/admin privilege.
Having said the obvious, the file extension nowadays is mainly used so that the OS can associate a program to that particular file (usually calling the program and passing the selected file as first parameter), and then it's up to the program to determine the file content.
It is a little bit different when talking about executable files. Under Unix, in order to be executable a file has to have the "x" flag set, otherwise it would not run, regardless of the extension. Under Windows, there is not such thing and the OS relies on only a few extensions (EXE, COM, BAT, etc.) to determine which files can be executed.
The EXE file, for example, has to start with "MZ" followed by some information for its allocation and size (http://www.delorie.com/djgpp/doc/exe/) and the OS surely checks its internal headers. Other formats (e.g. the COM executable format of the MS-DOS era) is just "pure" assembly code, so there is no check done by the OS. It just interprets those opcodes, hoping that everything will be fine.
So, to summarize:
File extension is mainly used so that the OS can call the appropriate program to open it (and passing the filename as the first parameter, argc/argv in C language for example)
Windows relies on some file extension to know if a file is executable, while Unix/Mac relies on a particular flag (x) associated with the file
Two things that are not well known about file extensions: directory names can have extension too, and extension can be way longer than the usual 3 characters.
With the help of file extension, you know how to read the first few and all the rest of the bytes. You also know what program to use to read the file. Or if it is an executable, you know that it is to be executed and not shown as a picture.
Yes you can change the file extension, but what does it mean then? It only means that OS (or any program that tried to read the file) is working correctly. Only you are providing bad data to it.
File extension is not something that some bytes of data inherently have. Extensions are given to those bytes depending upon the protocol followed to write them that way. After you have encoded the letters in binary form, you provide that binary form with .txt extension so that the text reader knows that these bytes convert to letters. That's the role of file extension. With bad file extension, this role is not fulfilled, resulting in incomprehension of the data you saved in binary.
As a general question: What's the role of file extension when determining file types?
The file extension usually identifies the application that opens a file.
If you rename a .JPG to a .PNG and while having JPG and PNG opened by the same application (usually an image viewer) that application can read the image stream and process it correctly regardless of having an incorrect file stream.
The problem arises if you rename the file in such a way that the file gets routed to an application that cannot handle the file's content.
If you rename a .DOCX (word) file to an Autocad extension (.DWG), opening the word file in autocad is likely to produce errors (unless per chance autocad can read word files).
I'm trying to solve the following problem. I want to create a set of directories with files in them , but in memory using C# , using strings / byte arrays, and I am trying to figure out what's the format and byte sequence for all of this. i mean something like
<magic sequence for top directory header> <magic sequence for file header> </ end file> ... file 2 file 3 ... etc ... </magic sequence for the directory header> , etc.
I'm talking about windows formats here.
Could you point me to a location where i can read about this or even better, give me some existing examples?
Thanks !
Angel
What you are looking depends on the filesystem in use. The filesystem defines how files and directories are stored. On windows a common format is FAT32 and NTFS (which is not publically available).
As shown in the link above, the FAT format is specified by Microsoft
I have a number of files that contain data in a format I am not familiar with. All of the data files begin with the same byte sequence, presumably a file header, and the sequence is "URES". I'm assuming that these files are some kind of resource file, perhaps a collection of data or other files all embedded into one file; that's just a guess however.
Does anyone know what format this is/might be?
If so, how would I interrogate the file? Are there applications that let me open these kind of files? Do you know of any libraries or APIs that I can use to gain programmatic access the data?
Have you tried running the unix file command on it?
I know of one file format that starts with URES. It's a data file used for Watchtower Library. I have yet to understand the format myself.
maybe its something from the Universal Resource Editor (URE) that comes with the OS/2 Toolkit? just a guess...
it is from the watchtower library files and they use meps to encode it which is thier own librarys and encryption software so to crack it would take you a long time.
I have a bunch of *.TBC files from a very old application that runs in MS-DOS called TURBOLAB. Anyone know which DB System use files with a TBC extension.
I've tried renaming the files to *.dbf to check if they are dBase files with no luck.
Any idea?
Judging by the application and era (old MS-DOS) *.tbc is probably a fixed length binary record format written by the application's developers.
Try opening up the file in a text editor like TextPad first and if you can read the contents, if so I have a fixed length text file reader that you can adapt to your needs. If you cannot you may need to determine field lengths and data types through trial and error.
Also, are there associated files for each *.tbc? A paired file could indicate field lengths and data types (or that information could be stored at the top of a *.tbc file itself).
I Googled this: FlexPro. I hope it helps. Sounds pricey, I hope your data is worth it.
Judging by the application and era
(old MS-DOS) *.tbc is probably a fixed
length binary record format written by
the application's developers.
I think you are right. Unfortunately there are no matching file names. If each of those files is a 'table', there are like ~150 tables in this database. Too much work for such an old app. I guess my customer will have to start from scratch using my app.
Thanks anyway for your help.