C++ Code to Access Linux Hard Disk Sectors (with a LoopBack Virtual Hard Disk)
Hi all,
I'm kind of new to programming in Linux & c/c++. I'm currently writing a FileManager using Ubuntu Linux(10.10) for Learning Purposes. I've got started on this project by creating a loopback device to be used as my virtual hard disk. After creating the loop back hard disk and mounting it has the following configuration.
Now what I want to do is develop a c++ program to read & write files to this loop back device,which I'm using to simulate an actual hard disk,at the blocks & sectors level. So far I've come up with the following code. But I'm still unable to read files from the hard disk one block at a time.
When I run this Program All what I get is the message for NULL.
"Error In Opening the HardDisk File Retuning Error...".
Could you please help me by pointing what am I doing wrong here ?. So I could open the loopback device as a file an access it at the sectors & block level.
Personally I'd use the open()/read()/write() calls instead of the stdio fopen()/fread()/fwrite() calls. You'll get more direct, unbuffered access; more useful error messages via perror() or errno; and a real file descriptor to call ioctl() on should you end up needing it. (which you might, dealing with block devices.)
Could you please give me an example code sample using the above 03 methods. A pointer to get me started on them ?. Because I feel I'll have to deal with the file descriptor at some point & I feel it wouldn't be optimum to do so using the <stdio.h> methods. could you give me some help for me to get started with the : open()/read()/write() please ??.
When we write a programme,we declare variables and compiler allocates memory to them.I want to get access to the physical block number of hard-disk where actually the data is stored by the programme "
Some one help me out... (3 Replies)
When we write a programme,we declare variables and compiler allocates memory to them.I want to get access to the physical block number of hard-disk where actually the data is stored by the programme "
Some one help me out... (1 Reply)
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