fat

programatically accessing the file allcoation table in windows

hi i want to know how can i programatically access the file allocation entries (FAT) in my windows operating system. I have read the articles which mention to read entries at a particular address in the harddisk, but how can i read those entries from the harddisk. I can try in C,C++,C# or VB. The tutorials on www.ntfs.com were helpful i...

Can anyone tell me what the authors mean on this line?

i was going through this link: FAT16 Basics to Assemble Clusters. I have read the structures involved in defining a directory entry in FAT. Now when giving the example for a FAT16 File, it says the data cluster is 0x03 for the example file MyFile.txt. Which means if we logically compute the Data Cluster we will be able to reach to the fi...

how to query a folder structure (files, directories)

I need to query folder structure. In other words I need to be able to access directory structure by SQL. I'm thinking of that there should be some OLE DB provider or some ODBC driver for that purpose. My friend said to google "folder monitoring" but I can't find anything Now I'm doing in command prompt dir>somefile and importing resulte...

Weird standard for FAT32 >4gb files

I have recently encountered an embedded system with IDE drives that are FAT32 but have >4gb files. It appears to do this by setting the file size in the 32byte directory entry to how many bytes the final cluster uses - instead of being the actual file size. This allows the the files to have arbitrary FAT chains. The downside is the only ...

There is in Windows file systems a pre computed hash for each file?

I want to search a file duplicate by its hash. For performance purposes I want to know if there is a stored hash/checksum for each file in NTFS/FAT file systems. If there is, I don't have to compute them all to search my file. If there is, how to access it using .NET? If it helps, it will be JPEG files. Do they have a checksum? ...

Verifying T-FAT on WinCE 5.0

We were having serious problems with corrupt files on our flash based FAT filesystem on WinCE 5.0. We believed that the files got corrupted because the WinCE device was turned off while writing to the FAT. Thus, we changed to T-FAT (transactional FAT). What is the least time consuming way of verifying that our problems are solved? ...

Fat ASP.NET MVC Controllers

Hello, I have been reading about "Fat Controllers" but most of the articles out there focus on pulling the service/repository layer logic out of the controller. However, I have run into a different situation and am wondering if anyone has any ideas for improvement. I have a controller with too many actions and am wondering how I can ...

Does the FAT filesystem have a signature?

Given the following BPB: The "MSWIN4.1" string is just the "OEM ID" field, and by Microsoft documentation it should not be used to identify FAT volumes. The "FAT32 " string is the BS_FilSysType field, and by Microsoft documentation it should not be used to identify FAT volumes either. So how do i identify that the volume is format...

Shrinking or partially truncating a file in DOS/FAT

I've been tasked with writing a data collection program for a Unitech HT630, which runs a proprietary DOS operating system that can run executables compiled for 16-bit MS DOS with some restrictions. I'm using the Digital Mars C/C++ compiler, which is working well thus far. One of the application requirements is that the data file must...

Where do filesystems like Reiser, NTFS, etc store the file tables?

Where do filesystems like Reiser, NTFS, etc store the file tables? We're looking at writing our own filesystem, and wondering if we should use a single file to hold it all using btree's or use something out there. Any advice? This is more a learning exercise than anything. Edit: removed NFS, and replaced with NTFS ...

Attributes in FAT (File allocation table)

Hi, Can someone please tell me where are the attributes per file allocated? Thanks ...

How can I use SD card for data logging 16bit data at 48ksps

Background My board incorporated an STM32 microcontroller with an SD/MMC card on SPI and samples analogue data at 48ksps. I am using the Keil Real-time Library RTX kernel, and ELM FatFs I have a high priority task that captures analogue data via DMA in blocks of 40 samples (40 x 16bit); the data is passed via a queue of length 128 (wh...

How to perform incremental tar backup of FAT filesystem

I use tar --listed-incremental=... to perform incremental backups on my computer, and for the most part it works like a charm. However, it doesn't seem to play well with my old FAT partition. It thinks that all the files have changed and backs up everything. I read somewhere that tar incremental backups rely on inodes, and that's why ...

FAT File system and lots of writes

I am considering using a FAT file system for an embedded data logging application. The logger will only create one file to which it continually appends 40 bytes of data every minute. After a couple years of use this would be over one million write cycles. MY QUESTION IS: Does a FAT system change the File Allocation Table every time a fil...